Thirty Years' War

The 1552 Peace of Passau sought to resolve the issues that led to conflict between Protestants and Catholics within the Holy Roman Empire, while the 1555 Peace of Augsburg tried to prevent their recurrence by fixing boundaries between the two faiths. Under the principle of cuius regio, eius religio, states were categorised as either Lutheran, then the most usual form of Protestantism, or Catholic, based on the religion of their ruler. Other provisions protected substantial religious minorities in cities like Donauwörth and confirmed Lutheran ownership of property taken from the Catholic Church since Passau.[21]

These agreements were undermined by the post-1555 expansion of Protestantism into areas previously designated as Catholic, as well as the growth of Reformed faiths not recognised by Augsburg, especially Calvinism, a theology viewed with hostility by both Lutherans and Catholics.[22] The Peace of Augsburg also gave individual rulers within the Empire greater political autonomy and control over the religion practised in their domains, while weakening central authority. Conflict over economic and political objectives frequently superseded religion, with Lutheran Saxony, Denmark-Norway and Sweden [lower-alpha 14] competing with each other and Calvinist Brandenburg over the Baltic trade.[24]

Reconciling these differences was hampered by the fragmented nature of the Empire and its representative institutions, which included 300 Imperial Estates distributed across Germany, the Low Countries, Northern Italy and modern France. They ranged in size and importance from the seven Prince-electors who voted for the Holy Roman Emperor, down to Prince-bishoprics and Imperial cities like Hamburg.[lower-alpha 15] Each also belonged to a regional grouping or "Imperial circle", which primarily focused on defence and operated as autonomous bodies. Above them sat the Imperial Diet, which prior to 1663 assembled on an irregular basis and largely served as a forum for discussion, rather than legislation.[25] [lower-alpha 16]

Although Emperors were elected, since 1440 the position had been held by a member of the House of Habsburg, the largest single landowner in the Holy Roman Empire with territories containing over eight million subjects, including Austria, Bohemia and Hungary. They also ruled Spain until 1556 when the two empires were divided, although Spain retained Imperial states such as Milan and Franche-Comté. While the Austrian and Spanish Habsburgs often worked together, their objectives did not always align. The Spanish Empire was a global maritime superpower whose possessions included the Spanish Netherlands, Milan, the Kingdom of Naples, the Philippines, and much of the Americas. In contrast, Austria was a land-based power, focused on ensuring their pre-eminence within Germany and securing their eastern border against the Ottoman Empire.[27]

Before Augsburg, unity of religion compensated for lack of strong central authority; once removed, it presented opportunities for those who sought to further weaken it. These included ambitious Imperial states like Lutheran Saxony and Catholic Bavaria, as well as France, confronted by Habsburg lands on its borders to the North, South, and along the Pyrenees. Since many foreign rulers were also Imperial princes, divisions within the Empire drew in external powers like Christian IV of Denmark, who joined the war in 1625 as Duke of Holstein-Gottorp.[23]

Habsburg possessions in Europe, ca. 1700

Disputes occasionally resulted in full-scale conflict like the 1583 to 1588 Cologne War, caused when its ruler converted to Calvinism. More common were events such as the 1606 'Battle of the Flags' in Donauwörth, when riots broke out after the Lutheran majority blocked a Catholic religious procession. Emperor Rudolf approved intervention by the Catholic Maximilian of Bavaria. In return, he was allowed to annex the town and as agreed at Augsburg, the official religion changed from Lutheran to Catholic.[28]

When the Imperial Diet opened in February 1608, both Lutherans and Calvinists united to demand formal re-confirmation of the Augsburg settlement. However, in return the Habsburg heir Archduke Ferdinand required the immediate restoration of all property taken from the Catholic church since 1555, rather than the previous practice whereby the court ruled case by case. This threatened all Protestants, paralysed the Diet, and removed the perception of Imperial neutrality.[29]

Loss of faith in central authority meant towns and rulers began strengthening their fortifications and armies; outside travellers often commented on the growing militarisation of Germany in this period.[30] This was taken a stage further in 1608 when Frederick IV, Elector Palatine formed the Protestant Union and Maximilian responded by setting up the Catholic League in July 1609. Both structures were primarily designed to support the dynastic ambitions of their leaders, but their creation combined with the 1609 to 1614 War of the Jülich Succession to increase tensions throughout the Empire.[31] Some historians who see the war as primarily a European conflict argue Jülich marks its beginning, with Spain and Austria backing the Catholic candidate, France and the Dutch Republic the Protestant.[32]

The Spanish Road
Purple: Spanish dependencies
Green: Ruled by Austria
Brown: Ruled by Spain

External powers became involved in what was an internal German dispute due to the imminent expiry of the 1609 Twelve Years' Truce, which suspended the Eighty Years War between Spain and the Dutch Republic. Before restarting hostilities, Ambrosio Spinola, commander in the Spanish Netherlands, needed to secure the Spanish Road, an overland route connecting Habsburg possessions in Italy to Flanders. This allowed him to move troops and supplies by road, rather than sea where the Dutch navy was dominant; by 1618, the only part not controlled by Spain ran through the Electoral Palatinate.[33]

Since Emperor Matthias had no surviving children, in July 1617 Philip III of Spain agreed to support Ferdinand's election as king of Bohemia and Hungary. In return, Ferdinand made concessions to Spain in Northern Italy and Alsace, and agreed to support their offensive against the Dutch. Delivering these commitments required his election as Emperor, which was not guaranteed; one alternative was Maximilian of Bavaria, who opposed the increase of Spanish influence in an area he considered his own, and tried to create a coalition with Saxony and the Palatinate to support his candidacy.[34]

A third candidate was the Calvinist Frederick V, Elector Palatine, who succeeded his father in 1610, then in 1613 married Elizabeth Stuart, daughter of James I of England. Four of the electors were Catholic, three Protestant; if this could be changed, it might result in a Protestant Emperor. When Ferdinand was elected king of Bohemia in 1617, he gained control of its electoral vote; however, his conservative Catholicism made him unpopular with the largely Protestant nobility, who were also concerned at the erosion of their rights. In May 1618, these factors combined to bring about the Bohemian Revolt.[35]

Cardinal Richelieu, who directed French foreign policy from 1624 until his death in 1642

By triggering direct French intervention, Nördlingen expanded the conflict rather than ending it. Richelieu provided the Swedes with new subsidies, hired mercenaries led by Bernard of Saxe-Weimar for an offensive in the Rhineland and in May 1635 formally declared war on Spain.[82] A few days later, the German states and Ferdinand agreed the Peace of Prague; in return for withdrawing the Edict of Restitution, the Heilbronn and Catholic Leagues were dissolved and replaced by a single Imperial army, although Saxony and Bavaria retained control of their own forces. This is generally seen as the point when the war ceased to be a primarily inter-German religious conflict.[83]

In March 1635, a French force entered the Valtellina, once again cutting the link between Spanish controlled Milan and the Empire.[84] In May, their main army of 35,000 invaded the Spanish Netherlands but was forced to retreat in July after suffering 17,000 casualties from disease and desertion. A Spanish offensive in 1636 reached Corbie in Northern France before lack of supplies forced them to retreat, and while it caused panic in Paris, the effort was not repeated.[85] In the March 1636 Treaty of Wismar, France formally joined the war in support of Sweden, whose loss of most of the territories gained by Gustavus along with their taxes made it increasingly reliant on French financing.[lower-alpha 18] Although further weakened by the defection of most of its German allies following the Peace of Prague, in June 1636 a Swedish army under Johan Banér entered Brandenburg and defeated an Imperial force at the Battle of Wittstock on 4 October, re-establishing their predominance in North-East Germany.[87]

Ferdinand II died in February 1637 and was succeeded by his son Ferdinand III, who faced a deteriorating military position. In March 1638, Bernard destroyed an Imperial army at Rheinfelden, while his capture of Breisach in December secured French control of Alsace and severed the Spanish Road. The main Imperial army under Matthias Gallas that had pushed Banér's Swedes back to the Baltic Coast was forced to divert resources against Bernard and to dispatch von Hatzfeldt against a Swedish-Palatine invading force in Westphalia. Though Hatzfeld defeated his opponents in October at Vlotho, the main army under Gallas had to retreat from the Baltic because of lack of supplies, partially dissolving in the process.[88] Banér defeated the Saxons at Chemnitz in April 1639, then entered Bohemia in May.[89] To retrieve the situation, Ferdinand diverted Piccolomini's army from Thionville, ending direct military cooperation between Austria and Spain.[90]

Pressure grew on Spanish minister Olivares to make peace, especially after attempts to hire Polish auxiliaries proved unsuccessful.[91] Cutting the Spanish Road had forced Madrid to resupply their armies in Flanders by sea and in October 1639 a large Spanish convoy was destroyed at the Battle of the Downs by a Dutch fleet, led by Maarten Tromp.[92] Dutch attacks on their possessions in Africa and the Americas caused unrest in Portugal, then part of the Spanish Empire and combined with heavy taxes caused revolts in Portugal and Catalonia.[93] After the French captured Arras in August 1640 and overran Artois, Olivares argued it was time to accept Dutch independence and prevent further losses in Flanders. Spain remained a formidable power but could no longer subsidise Ferdinand, impacting his ability to continue the war.[94]

Breitenfeld

Wolfenbüttel

Wittstock

Nördlingen

Breisach

Rheinfelden

Zusmarshausen

Münster

Freiberg

Herbsthausen

Vlotho

Osnabrück

Tuttlingen

Hamburg

Prague

Kempen

Leipzig

Thionville

Chemnitz

Regensburg

Halberstadt

Freiburg [lower-alpha 20]

Germany, 1635 to 1648; key locations mentioned in text

After Bernard died in July 1639, his troops joined Banér's Swedish army on an ineffectual campaign along the Weser, the highlight being a surprise attack in January 1641 on the Imperial Diet in Regensburg.[95] Forced to retreat, Banér reached Halberstadt in May where he died; despite beating off an Imperial force at Wolfenbüttel in June, his largely German troops mutinied due to lack of pay.[96] The situation was saved by the arrival of Lennart Torstenson in November with 7,000 Swedish recruits and enough cash to satisfy the mutineers.[97]

French victory at Kempen in January 1642 was followed by Second Breitenfeld in October 1642, where Torstenson inflicted almost 10,000 casualties on an Imperial army led by Archduke Leopold Wilhelm of Austria.[98] The capture of Leipzig in December gave the Swedes a significant new base in Germany, and despite their failure to take Freiberg,[99] by 1643 the Saxon army had been reduced to a few isolated garrisons.[100] While Ferdinand accepted a military solution was no longer possible, by fighting on he hoped to prevent the Imperial Estates joining his peace negotiations with France and Sweden, thus preserving his authority by allowing him to represent the Empire as a whole.[101]

This seemed more achievable with the deaths of Richelieu in December 1642, followed by Louis XIII on 14 May 1643, leaving his five-year-old son Louis XIV as king. However, Richelieu's policies were continued by his successor Cardinal Mazarin, while French gains in Alsace allowed him to re-focus on the war against Spain in the Netherlands. On 19 May, Condé won an emphatic victory over the Spanish at Rocroi. Although his success was less significant than often assumed,[102] since it had no immediate effect on Spanish control of the Southern Netherlands and the Spanish veterans captured at Rocroi were quickly exchanged, it ended all chances of launching another invasion of France from the Low Countries.[103]

Condé's inability to take full advantage of Rocroi was partially due to factors that affected all the combatants. The devastation inflicted by 25 years of warfare meant armies spent more time foraging than fighting, forcing them to become smaller and more mobile with a much greater emphasis on cavalry. It also shortened the campaigning seasons, since the need to gather forage meant they started later, and restricted them to areas that could be easily supplied, usually close to rivers.[104] In addition, the French had to rebuild their army in Germany after it was shattered by an Imperial-Bavarian force led by Franz von Mercy at Tuttlingen in November.[105]

Soon after Rocroi, Ferdinand invited Sweden and France to attend peace talks in the Westphalian towns of Münster and Osnabrück,[106] but these were delayed when Christian of Denmark blockaded Hamburg and increased toll payments in the Baltic.[107] This severely impacted the Dutch and Swedish economies and in December 1643 the Swedes began the Torstenson War by invading Jutland, with the Dutch providing naval support. Ferdinand pulled together an Imperial army under Gallas to attack the Swedes from the rear, which proved a disastrous decision. Leaving Wrangel to finish the war in Denmark, in May 1644 Torstenson marched into the Empire; Gallas was unable to stop him, while the Danes sued for peace after their defeat at Fehmarn in October 1644.[108]

In August 1644, the French and Bavarian armies met in the three day Battle of Freiburg, in which both sides suffered heavy casualties but is generally viewed as a narrow Bavarian victory. His losses convinced Maximilian the war could no longer be won and he now put pressure on Ferdinand to end the conflict.[109] Shortly after peace talks restarted in November, Gallas' Imperial army disintegrated and the remnants retreated into Bohemia, where they were scattered by Torstenson at Jankau in March 1645.[110] In May, a Bavarian force under von Mercy destroyed a French detachment at Herbsthausen, before he was defeated and killed at Second Nördlingen in August.[111] With Ferdinand unable to help, John George of Saxony signed a six-month truce with Sweden in September, followed by the March 1646 Treaty of Eulenberg in which he agreed to remain neutral until the end of the war.[112]

The final battle of the war; Swedish siege of Prague

Under Turenne, French commander in the Rhineland, and Wrangel, who had replaced Torstenson, the French and Swedes separately invaded Bavaria in the summer of 1646.[113] Maximilian was soon desperate to end the war he was largely responsible for starting, at which point the Spanish publicised a secret offer by Mazarin to exchange French-occupied Catalonia for the Spanish Netherlands. Angered by this duplicity, the Dutch agreed a truce with Spain in January 1647 and began to negotiate their own peace terms.[114] Having failed to acquire the Netherlands through diplomacy, Mazarin decided to do so by force and to free up resources, on 14 March 1647 he signed the Truce of Ulm with Bavaria, Cologne and Sweden.[115]

The offensive was to be led by Turenne, but the plan fell apart when his mostly German troops mutinied, while Bavarian general Johann von Werth refused to comply with the truce.[116] Although the mutinies were quickly suppressed, Maximilian felt obliged to follow Werth's example and in September ordered Bronckhorst-Gronsfeld to combine the remnants of the Bavarian army with Imperial troops under von Holzappel.[117] Outnumbered by a Franco-Swedish army led by Wrangel and Turenne, they were defeated at Zusmarshausen in May 1648 and von Holzappel was killed. Although the bulk of the Imperial army escaped thanks to an effective rearguard action by Raimondo Montecuccoli, Bavaria was left defenceless once again.[118]

The Swedes sent a second force under von Königsmarck to attack Prague, seizing the castle and Malá Strana district in July. The main objective was to gain as much loot as possible before the war ended; they failed to take the Old Town but captured the Imperial library, along with treasures including the Codex Gigas, now in Stockholm. When a Spanish offensive in Flanders ended with defeat at Lens in August 1648, Ferdinand finally agreed terms and on 24 October, he signed peace treaties with France and Sweden, ending the war.[119]

Holy Roman Empire after the Peace of Westphalia, 1648

The Peace of Westphalia actually consisted of three separate agreements; the Peace of Münster between Spain and the Dutch Republic, the Treaty of Osnabrück between the Empire and Sweden, plus the Treaty of Münster between the Empire and France. Preliminary discussions began in 1642 but only became serious in 1646; a total of 109 delegations attended at one time or other, with talks split between Münster and Osnabrück. After the Swedes rejected Christian of Denmark as mediator, the negotiators finally agreed on Papal Legate Fabio Chigi and the Venetian envoy Alvise Contarini.[139]

The Peace of Münster was the first to be signed on 30 January 1648 and is considered to be part of the Westphalia settlement since the Dutch Republic was still technically part of the Spanish Netherlands and thus Imperial territory. The treaty confirmed Dutch independence, although the Imperial Diet did not formally accept that it was no longer part of the Empire until 1728.[140] The Dutch were also given a monopoly over trade conducted through the Scheldt estuary, ensuring the commercial ascendancy of Amsterdam; Antwerp, capital of the Spanish Netherlands and previously the most important port in Northern Europe, would not recover until the late 19th century.[141]

Negotiations with France and Sweden were conducted in conjunction with the Imperial Diet, and were multi-sided discussions involving many of the German states. This resulted in the treaties of Münster and Osnabrück, making peace with France and Sweden respectively. Ferdinand resisted signing until the last possible moment, doing so on 24 October only after a crushing French victory over Spain at Lens, and with Swedish troops on the verge of taking Prague.[142] It has been argued they were a "major turning point in German and European...legal history", because they went beyond normal peace settlements and effected major constitutional and religious changes to the Empire itself.[143]

Key elements of the Peace were provisions confirming the autonomy of states within the Empire, including Ferdinand's acceptance of the supremacy of the Imperial Diet, and those seeking to prevent future religious conflict. Article 5 reconfirmed the Augsburg settlement, established 1624 as the basis, or "Normaljahr", for determining the dominant religion of a state and guaranteed freedom of worship for religious minorities. Article 7 recognised Calvinism as a Reformed faith and removed the ius reformandi, the requirement that if a ruler changed his religion, his subjects had to follow suit. These terms did not apply to the hereditary lands of the Habsburg monarchy, such as Lower and Upper Austria.[144]

Signing of the Peace of Münster between Spain and the Dutch Republic, 30 January 1648.

In terms of territorial concessions, Brandenburg-Prussia received Farther Pomerania, and the bishoprics of Magdeburg, Halberstadt, Kammin, and Minden. Frederick's son Charles Louis regained the Lower Palatinate and became the eighth Imperial elector, although Bavaria kept the Upper Palatinate and its electoral vote.[140] Externally, the treaties formally acknowledged the independence of the Dutch Republic and the Swiss Confederacy, effectively autonomous since 1499. In Lorraine, the Three Bishoprics of Metz, Toul and Verdun, occupied by France since 1552, were formally ceded, as were the cities of the Décapole in Alsace, with the exception of Strasbourg and Mulhouse.[112] Sweden received an indemnity of five million thalers, the Imperial territories of Swedish Pomerania, and the Prince-bishoprics of Bremen and Verden, which also gave them a seat in the Imperial Diet.[145]

The Peace was later denounced by Pope Innocent X, who regarded the bishoprics ceded to France and Brandenburg as property of the Catholic church, and thus his to assign.[146] It also disappointed many exiles by accepting Catholicism as the dominant religion in Bohemia, Upper and Lower Austria, all of which were Protestant strongholds prior to 1618. Fighting did not end immediately, since demobilising over 200,000 soldiers was a complex business, and the last Swedish garrison did not leave Germany until 1654.[147] In addition, Mazarin insisted on excluding the Burgundian Circle from the treaty of Münster, allowing France to continue its campaign against Spain in the Low Countries, a war that continued until the 1659 Treaty of the Pyrenees. The political disintegration of Poland-Lithuania led to the 1655 to 1660 Second Northern War with Sweden, which also involved Denmark, Russia and Brandenburg, while two Swedish attempts to impose its control on the port of Bremen failed in 1654 and 1666.[148]

It has been argued the Peace established the principle known as Westphalian sovereignty, the idea of non-interference in domestic affairs by outside powers, although this has since been challenged. The process, or 'Congress' model, was adopted for negotiations at Aix-la-Chapelle in 1668, Nijmegen in 1678, and Ryswick in 1697; unlike the 19th century 'Congress' system, these were to end wars, rather than prevent them, so references to the 'balance of power' can be misleading.[149]

Historians often refer to the 'General Crisis' of the mid-17th century, a period of sustained conflict in states such as China, the British Isles, Tsarist Russia and the Holy Roman Empire. In all these areas, war, famine and disease inflicted severe losses on local populations.[150] While the Thirty Years War certainly ranks as one of the worst of these events, 19th century nationalists often increased or exaggerated its impact to illustrate the dangers of a divided Germany.[151] Suggestions of up to 12 million deaths from a population of 18 million are no longer accepted, while claims of material losses are either not supported by contemporary evidence or in some cases exceed prewar tax records.[152]

Population declines within Germany 1618 to 1648
Note; Decline includes factors such as emigration from rural to more secure urban areas and does not equate to Deaths

  33–66%

  > 66%

The conflict has been described as one of the greatest medical catastrophes in history but by modern standards the number of soldiers involved was relatively low.[153] Battles generally featured armies of around 13,000 to 20,000 each, the largest being Alte Veste in 1632 with a combined 70,000 to 85,000. Estimates of the total deployed by both sides within Germany range from an average of 80,000 to 100,000 from 1618 to 1626, peaking at 250,000 in 1632 and falling to under 160,000 by 1648.[154] Casualty rates could be extremely high; of 230 men conscripted from the Swedish village of Bygdeå between 1621 and 1639, 215 are recorded as dead or missing, while another five returned home crippled.[14]

Aggregating figures from known battles and sieges, historian Peter Wilson estimates those either killed or wounded in combat totalled around 450,000. Since research shows disease either killed or incapacitated two to three times that number, that would suggest military casualties ranged from 1.3 to 1.8 million dead or otherwise rendered unfit for service.[13] Pitirim Sorokin calculates an upper limit of 2,071,000 military casualties,[155] although his methodology has been disputed. In general, historians agree the war was an unprecedented mortality disaster and the vast majority of casualties, whether civilian or military, took place after Swedish intervention in 1630.[156]

Based on local records, military action accounted for less than 3% of civilian deaths, with the major causes being starvation (12%), bubonic plague (64%), typhus (4%), and dysentery (5%).[157] Although regular outbreaks of disease were common for decades prior to 1618, the conflict greatly accelerated their spread, due to the influx of soldiers from foreign countries, the shifting locations of battle fronts and displacement of rural populations into already crowded cities.[158] This was not restricted to Germany; disease carried by French and Imperial soldiers allegedly sparked the 1629–1631 Italian plague, the "worst mortality crisis to affect Italy during the Early modern period",[159] leading to some 280,000 deaths, with higher estimates of around 1 million.[160] Poor harvests throughout the 1630s and repeated plundering of the same areas led to widespread famine; contemporaries record people eating grass, or too weak to accept alms, while instances of cannibalism were common.[161]

The modern consensus is the population of the Holy Roman Empire declined from 18 to 20 million in 1600 to 11 to 13 million in 1650, and did not regain pre-war levels until 1750.[162] Nearly 50% of these losses appear to have been incurred during the first period of Swedish intervention from 1630 to 1635. The high mortality rate compared to the Wars of the Three Kingdoms in Britain may partly be due to the reliance of all sides on foreign mercenaries, often unpaid and required to live off the land.[163] Lack of a sense of 'shared community' resulted in atrocities such as the destruction of Magdeburg, in turn creating large numbers of refugees who were extremely susceptible to sickness and hunger. While flight saved lives in the short-term, in the long run it often proved catastrophic.[164]

Soldiers plundering a farm

In 1940, agrarian historian Günther Franz published a detailed analysis of regional data from across Germany covering the period from 1618 to 1648. Broadly confirmed by more recent work, he concluded "about 40% of the rural population fell victim to the war and epidemics; in the cities,...33%".[17] These figures can be misleading, since Franz calculated the absolute decline in pre and post-war populations, or 'total demographic loss'. They therefore include factors unrelated to death or disease, such as permanent migration to areas outside the Empire or lower birthrates, a common but less obvious impact of extended warfare.[165] There were also wide regional variations; some areas in Northwest Germany were relatively peaceful after 1630 and experienced almost no population loss, while those of Mecklenburg, Pomerania and Württemberg fell by nearly 50%.[152]

Although some towns may have overstated their losses to avoid taxes, individual records confirm serious declines; from 1620 to 1650, the population of Munich fell from 22,000 to 17,000, that of Augsburg from 48,000 to 21,000.[166] The financial impact is less clear; while the war caused short-term economic dislocation, especially in the period 1618 to 1623, overall it accelerated existing changes in trading patterns. It does not appear to have reversed ongoing macro-economic trends, such as the reduction of price differentials between regional markets, and a greater degree of market integration across Europe.[167] The death toll may have improved living standards for the survivors; one study shows wages in Germany increased by 40% in real terms between 1603 and 1652.[168]

Innovations made during the war by Gustavus in particular are considered part of the tactical evolution known as the "Military Revolution", although there is some debate as to whether tactics or technology were at the heart of these changes.[169] These developments were popularised by Maurice of Orange in the 1590s and sought to increase infantry firepower by moving from massed columns to line formation. Gustavus refined these changes by reducing the ten ranks used by Maurice to six, while increasing the proportion of Musketeers to pikemen; in addition, each unit was equipped with quick-firing light artillery pieces on either flank. Perhaps the best example of their application in real life was the defeat of Tilly's traditionally organised army by the Swedes at Breitenfeld in September 1631.[170]

Breitenfeld 1631; Tilly's army (left) are deployed two companies deep, the Swedes (right) just one company deep

Line formations were not always successful, as demonstrated by the victory of the supposedly obsolete Spanish tercios over the "new model" Swedish army at Nördlingen in 1634.[171] They were also harder to co-ordinate in offensive operations; Gustavus compensated by requiring his cavalry to be far more aggressive, often employing his Finnish light cavalry or Hakkapeliitta as shock troops. He also used columns on occasion, including the failed assault at Alte Veste in September 1632. Columns continued to be viewed as more effective in offensive operations and were used by Napoleon throughout the latter stages of the Napoleonic Wars.[172]

Such tactics needed professional soldiers, who could retain formation, reload and fire disciplined salvos while under attack, as well as the use of standardised weapons. The first half of the 17th century saw the publication of numerous instruction manuals showing the movements required, thirty-two for pikemen and forty-two for musketeers.[173] The period needed to train an infantryman who could operate in this way was estimated as six months, although in reality many went into battle with far less experience.[174] It also placed greater responsibility on junior officers who provided the vital links between senior commanders and the tactical unit. One of the first military schools designed to produce such men was set up at Siegen in 1616 and others soon followed.[174]

On the other hand, strategic thinking failed to develop at the same pace. Historian Jeremy Black claims most campaigns were "inconclusive" and almost exclusively concerned with control of territory, rather than focused strategic objectives. The lack of connection between military and diplomatic goals helps explain why the war lasted so long and why peace proved so elusive.[175] There were a number of reasons for this. When the Treaty of Westphalia was signed in 1648, the Franco-Swedish alliance still had over 84,000 men under arms on Imperial territory, their opponents around 77,000; while relatively small in modern terms, such numbers were unprecedented at the time.[176] With the possible exception of Spain, the 17th century state could not support armies of this size, forcing them to depend on "contributions" levied or extorted from areas they passed through.[177]

Obtaining supplies thus became the limiting factor in campaign planning, an issue that grew more acute later in the war when much of the Empire had already been fought over. Even when adequate provisions could be gathered, the next problem was getting them to the troops; to ensure security of supply, commanders were forced to stay close to rivers, then the primary means of bulk transportation, and could not move too far from their main bases.[178] Many historians argue feeding the troops became an objective in itself, unconnected to diplomatic goals and largely uncontrolled by their central governments. The result was "armies increasingly devoid of intelligible political objectives...degenerating into travelling armed mobs living in a symbiotic relationship with the countryside they passed through".[179] This lack of connection often worked against the political aims of their employers; the devastation inflicted in 1628 and 1629 by Imperial troops on Brandenburg and Saxony, both nominally their allies, was a major factor in their support for Swedish intervention.[180]

It has been suggested the breakdown of social order caused by the war was often more significant and longer lasting than the immediate damage.[181] The collapse of local government created landless peasants, who banded together to protect themselves from the soldiers of both sides, and led to widespread rebellions in Upper Austria, Bavaria and Brandenburg. Soldiers devastated one area before moving on, leaving large tracts of land empty of people and changing the ecosystem. Food shortages were worsened by an explosion in the rodent population; Bavaria was overrun by wolves in the winter of 1638, and its crops destroyed by packs of wild pigs the following spring.[182]

A peasant begs for mercy in front of his burning farm; by the 1630s, being caught in the open by soldiers from either side was 'tantamount to a death sentence'[158]

Contemporaries spoke of a 'frenzy of despair' as people sought to make sense of the relentless and often random bloodshed unleashed by the war. Attributed by religious authorities to divine retribution for sin, other attempts to identify a supernatural cause led to a series of Witch-hunts, beginning in Franconia in 1626 and quickly spreading to other parts of Germany.[183] They began in the Bishopric of Würzburg, an area with a history of such events going back to 1616 and now re-ignited by Bishop von Ehrenberg, a devout Catholic eager to assert the church's authority in his territories. By the time he died in 1631, over 900 people from all levels of society had been executed.[184]

The Bamberg witch trials, held in the nearby Bishopric of Bamberg from 1626 to 1631, claimed over one thousand lives; in 1629, 274 died in the Eichstätt witch trials, plus another 50 in the adjacent Duchy of Palatinate-Neuburg.[185] Elsewhere, persecution followed Imperial military success, expanding into Baden and the Palatinate following their reconquest by Tilly, then into the Rhineland.[186] However, the extent to which they were symptomatic of the impact of the conflict on society is debatable, since many took place in areas relatively untouched by the war. Concerned their brutality would discredit the Counter-Reformation, Ferdinand ensured active persecution largely ended by 1630.[187]

Although the war caused immense destruction, it has also been credited with sparking a revival in German literature, including the creation of societies dedicated to "purging of foreign elements" from the German language.[188] One example is Simplicius Simplicissimus, often suggested as one of the earliest examples of the Picaresque novel; written by Hans Jakob Christoffel von Grimmelshausen in 1668, it includes a realistic portrayal of a soldier's life based on his own experiences, many of which are verified by other sources.[189] Other less famous examples include the diaries of Peter Hagendorf, a participant in the Sack of Magdeburg whose description of the everyday brutalities of the war remain compelling.[190]

For German, and to a lesser extent Czech writers, the war continued to be remembered as a defining moment of national trauma, the 18th century poet and playwright Friedrich Schiller being one of many to use it in their work. Variously known as the 'Great German War,' 'Great War' or 'Great Schism', for 19th and early 20th century German nationalists it showed the dangers of a divided Germany and was used to justify the creation of the German Empire in 1871, as well as the Greater Germanic Reich envisaged by the Nazis.[191] Bertolt Brecht used it as the backdrop for his 1939 anti-war play Mother Courage and Her Children, while its enduring cultural resonance is illustrated by the novel Tyll; written by Austro-German author Daniel Kehlmann and also set during the war, it was nominated for the 2020 Booker Prize.[192]

Europe after the Peace of Westphalia, 1648

The Peace reconfirmed "German liberties", ending Habsburg attempts to convert the Holy Roman Empire into a more centralised state similar to Spain. Over the next 50 years, Bavaria, Brandenburg-Prussia, Saxony and others increasingly pursued their own policies, while Sweden gained a permanent foothold in the Empire. Despite these setbacks, the Habsburg lands suffered less from the war than many others and became a far more coherent bloc with the absorption of Bohemia, and restoration of Catholicism throughout their territories.[193]

By laying the foundations of the modern nation state, Westphalia changed the relationship between subjects and their rulers. Previously, many had overlapping, sometimes conflicting, political and religious allegiances; they were now understood to be subject first and foremost to the laws and edicts of their respective state authority, not the claims of any other entity, religious or secular. This made it easier to levy national forces of significant size, loyal to their state and its leader; one lesson learned from Wallenstein and the Swedish invasion was the need for their own permanent armies, and Germany as a whole became a far more militarised society.[194]

The benefits of Westphalia for the Swedes proved short-lived. Unlike French gains which were incorporated into France, Swedish territories remained part of the Empire, and they became members of the Lower and Upper Saxon kreis. While this gave them seats in the Imperial Diet, it also brought them into direct conflict with both Brandenburg-Prussia and Saxony, their competitors in Pomerania. The income from their imperial possessions remained in Germany and did not benefit the kingdom of Sweden; although they retained parts of Swedish Pomerania until 1815, much of it was ceded to Prussia in 1679 and 1720.[195]

Swedish sovereignty over Western Pomerania (in blue) was confirmed in 1653

France arguably gained more from the Thirty Years' War than any other power; by 1648, most of Richelieu's objectives had been achieved. These included separation of the Spanish and Austrian Habsburgs, expansion of the French frontier into the Empire, and an end to Spanish military supremacy in Northern Europe.[196] Although the Franco-Spanish conflict continued until 1659, Westphalia allowed Louis XIV to begin replacing Spain as the predominant European power.[197]

While differences over religion remained an issue throughout the 17th century, it was the last major war in Continental Europe in which it can be said to be a primary driver; later conflicts were either internal, such as the Camisards revolt in South-Western France, or relatively minor like the 1712 Toggenburg War.[198] It created the outlines of a Europe that persisted until 1815 and beyond; the nation-state of France, the beginnings of a unified Germany and separate Austro-Hungarian bloc, a diminished but still significant Spain, independent smaller states like Denmark, Sweden and Switzerland, along with a Low Countries split between the Dutch Republic and what became Belgium in 1830.[195]