Italian War of 1551–1559

Henry II remitting the Order of Saint-Michel to Marshall de Tavannes after the Battle of Renty, on 13 August 1554

Henry II sealed a treaty with Suleiman the Magnificent in order to cooperate against the Habsburgs in the Mediterranean.[4] This was triggered by the conquest of Mahdiya by the Genoese Admiral Andrea Doria on 8 September 1550, for the account of Charles V. The alliance allowed Henry II to push for French conquests towards the Rhine, while a Franco-Ottoman fleet defended southern France.[5]

The 1551 Ottoman Siege of Tripoli was the first step of the all-out Italian War of 1551–59 in the European theater, and in the Mediterranean the French galleys of Marseille were ordered to join the Ottoman fleet.[6] In 1552, when Henry II attacked Charles V, the Ottomans sent 100 galleys to the Western Mediterranean,[7] which were accompanied by three French galleys under Gabriel de Luetz d'Aramon in their raids along the coast of Calabria in Southern Italy, capturing the city of Reggio.[8] In the Battle of Ponza in front of the island of Ponza, the fleet met with 40 galleys of Andrea Doria, and managed to vanquish the Genoese and capture seven galleys. This alliance would also lead to the combined Invasion of Corsica in 1553. The Ottomans continued harassing the Habsburg possessions with various operations in the Mediterranean, such as the Ottoman invasion of the Balearic islands in 1558, following a request by Henry II.[9]

On the continental front, the opening phase of the war was marked by the Parmesan succession crisis: the newly elected Pope Julius III had confirmed Ottavio Farnese as the Duke of Parma and Piacenza, while Charles V's Imperial troops had occupied the city in 1547 after Ottavio's father's assassination. Seeing France as his best choice against the Emperor, Ottavio Farnese signed a defensive alliance with Henry II of France on 27 May 1551, placing Parma under French protection. Charles could not accept this, and pressured the Pope into an alliance against France and Parma, causing the War of Parma in June 1551. The main combat of this phase was the Siege of Mirandola (1551), during which the Franco-Farnese defenders repulsed attacks by the Papal-Imperial-Spanish forces. The belligerents agreed to a two-year truce on 29 April 1552, ratified by Charles V on 10 May, which ended the War of Parma.

Meanwhile, Henry II allied with German Protestant princes against Charles V with the Treaty of Chambord on 15 January 1552. An early offensive into Lorraine, in the Second Schmalkaldic War, was successful, with Henry capturing the Three Bishoprics of Metz, Toul, and Verdun and securing them by defeating the invading Habsburg army at the Battle of Renty (12 August 1554). In 1552, an anti-Spanish revolt in the Republic of Siena gave Henry another ally; on 17 July 1552, a Franco-Sienese army managed to expel the Spanish garrison. The Sienese welcomed a French garrison to defend the Republic against Spanish recapture attempts. A French army invaded Tuscany in 1553 in support of the Sienese Republic. In January 1554, the Spanish started besieging the city of Siena. The French troops were attacked by an Imperial‐Florentine army and defeated at the Battle of Marciano by Gian Giacomo Medici (2 August 1554). After an 18-month-long siege, Siena fell to Spanish forces on 15 April 1555. Although a Republic of Siena reconstituted in Montalcino run by exiled Sienese loyalists continued to exist until 3 April 1559, the territory of the Republic of Siena was fully annexed to the Duchy of Florence under Cosimo I de' Medici with the Treaty of Cateau-Cambrésis (3 April 1559), and eventually became part of the Grand Duchy of Tuscany (1569).[10]

A treaty in Vaucelles was signed on 5 February 1556 between Charles V and Henry II of France.[11] After Emperor Charles' abdication in 1556 split the Habsburg empire between Philip II of Spain and Ferdinand I, the focus of the war shifted to Flanders. However, the truce was broken shortly afterwards. Pope Paul IV was displeased and urged Henry II to join the Papal States in an invasion of Spanish Naples. On 1 September 1556, Philip II responded by pre-emptively invading the Papal States with 12,000 men under the Duke of Alba. French forces approaching from the north were defeated and forced to withdraw at the Siege of Civitella in August 1557.[12] Philip, in conjunction with Emmanuel Philibert, Duke of Savoy, defeated the French in the Battle of St. Quentin (1557) (10–27 August). The Spanish attempted to blockade Rome by occupying the port of Ostia but were driven back by the Papal armies in a surprise attack. However, when French troops were unable to come to their aid, the Papal armies were left exposed and were defeated, with Spanish troops under the Duke of Alba arriving at the edge of Rome. Out of fear of another sack of Rome, Paul IV agreed to the Duke of Alba's demand for the Papal States to declare neutrality by signing the Peace of Cave-Palestrina (12 September 1557). Emperor Charles V criticized the peace agreement as being overly generous to the Pope.[13]

A brief French-backed revolt led by Thomas Stafford against queen Mary I of England resulted in a three-day siege of Scarborough Castle in April 1557. Mary declared war on France in June 1557 and English troops assisted in the victory at St. Quentin in August. But England's entry into the war provoked the French Siege of Calais in January 1558, which was a defeat for the English. French armies plundered Spanish possessions in the Low Countries and emerged victorious in the Siege of Thionville (April–June 1558). Nonetheless, Henry lost gravely at the Battle of Gravelines (13 July 1558) and was forced to accept a peace agreement in which he renounced any further claims to Italy.[10]

The wars ended for other reasons, including "the Double Default of 1557", when the Spanish Empire, followed quickly by the French, defaulted on its debts. In addition, Henry II had to confront a growing Protestant movement at home, which he hoped to crush.[14]

Oman (1937) argues that the inconclusive campaigns which generally lack a decisive engagement were largely due to ineffective leadership and lack of offensive spirit. He notes that mercenary troops were used too often and proved unreliable. Hale emphasizes the defensive strength of bastion forts newly designed at angles to dissipate cannon fire. Cavalry, which had traditionally used shock tactics to overawe the infantry, largely abandoned it and relied on pistol attacks by successive ranks of attackers. Hale notes the use of old-fashioned mass formations, which he attributes to lingering conservatism. Overall, Hale emphasizes new levels of tactical proficiency.[15]

In 1552 Charles V had borrowed over 4 million ducats, with the Metz campaign alone costing 2.5 million ducats. Shipments of treasure from the Indies totalled over two million ducats between 1552 and 1553. By 1554, the cash deficit for the year was calculated to be over 4.3 million ducats, even after all tax receipts for the six ensuing years had been pledged and the proceeds spent in advance. Credit at this point began costing the crown 43 percent interest (largely financed by the Fugger and Welser banking families). By 1557 the crown was refusing payment from the Indies since even this was required for payment of the war effort (used in the offensive and Spanish victory at the battle of St. Quentin in August 1557).[16]

French finances during the war were mainly financed by the increase in the taille tax, as well as indirect taxes like the gabelle and customs fees. The French monarchy also resorted to heavy borrowings during the war from financiers at rates of 10–16 percent interest.[17] The taille was estimated in collection for 1551 at around six million livres.

During the 1550s, Spain had an estimated military manpower of around 150,000 soldiers, whereas France had an estimated manpower of 50,000.[17]

Italy after the Treaties of Cateau-Cambrésis

The Treaty of Cateau-Cambrésis (1559) consisted of two treaties: the first one was signed between Elizabeth I of England and Henry II of France on April 2; the second one was signed between Henry II of France and Philip II of Spain on April 3.[18] The two treaties also defined the conclusion of the Imperial-French wars and therefore the end of the Habsburg-Valois conflict as a whole, with the approval of Ferdinand I, Holy Roman Emperor.[lower-alpha 1][lower-alpha 2] The four monarchs did not meet in person but were represented by ambassadors and delegations.[22] Some Italian states also attended the conference.[23]