John of Gaunt's chevauchée of 1373

In spite of the modification of the plan and the lack of interest from John of Brittany for the new itinerary, the latter joined his forces to those of Lancaster, probably half-heartedly. The responsibility of going by sea to support Neville and Knolles at Brest, who by now had to eat their own horses, went to the Earl of Salisbury.[3] They landed at Calais at the beginning of July 1373. There they gathered, until on August 9, brought by a fleet of more than a hundred ships requisitioned in the eastern harbours of the island or chartered in Holland and Flanders,[3] an army of 6,000 archers and 3,000 men-at-arms (including 1800 Scottish mercenaries), accompanied by 2,000 non-combatants. The troops were commanded by the Constable Edward Despenser, assisted by the Marshals Thomas Beauchamp and William Ufford.[6] Several English noblemen were with them, like Henry Percy, 1st Earl of Northumberland, and several prestigious captains as Hugh Calveley or Walter Hewitt.[3]

The reconquest by Charles V of the territories conceded by the treaty of Brétigny in 1360. In yellow, John of Gaunt's chevauchée in 1373.

We were in August when, banners all unfurled, a Wednesday morning, Froissart tells us, the troops left Calais, separated in two columns. The one of John IV marching southward, towards Hesdin, to make junction at the river Somme east of Amiens. The other, led by John of Gaunt, marching 60 km further east.[3] He passed in front of Guînes and Ardres, which were allied to him. For the first night of bivouacking, the English camp stretched over several miles, between Balinghem and Licques. On the next day, the soldiers rode to Saint-Omer, held by a vassal of the king of France. There, a few hours later at Thérouanne where 1200 French soldiers were gathered, no fight was engaged, each side observing the enemy beyond the fortifications.[6]

The column advanced around ten kilometers a day, pillaging and burning on a 20 km (12 mi) wide front. At the vanguard walked the troops commanded by the Marshals, followed by the group under orders from the two Dukes. Behind were the supply chariots. Finally, the Constable's army closed the march.[6] The width of the front was a consequence of the need to sufficiently supply the men in food, but offered the disadvantage of having the groups dispersed, at the mercy of attacks from the French cavalry, or even peasants.

This is how, on the following days, the invaders confronted French soldiers in Artois, in the outskirts of Aire-sur-la-Lys and Saint-Pol-sur-Ternoise. A violent skirmish happened before the walls of Doullens, which was almost captured. Around August 19, the two Dukes made junction on the Somme,[3] after John of Gaunt, passing next to Arras, also failed to take Bray-sur-Somme.[7]

In the meantime in Amiens, in the French camp, Philip the Bold was completing his army to face them. Charles V had also called in reinforcement the troops of the captains stationed in Brittany: Bertrand du Guesclin, temporarily blocked in Derval, and with him, Olivier de Clisson, nicknamed the Butcher, the Viscount of Rohan, Jean de Bueil, etc.[6] In Ribemont-sur-Ancre, the latter, supported by the lords of Chin and Bousies and 120 soldiers, attacked 80 soldiers of Hugh of Calveley, routing them.[7] Continuing on their destructive path, the invaders set Roye on fire, whose inhabitants had sought refuge inside the fortified church.[3]

Around 3 September, the Dukes spent three days in Vaux-sur-Laon, a suburb of Laon, while their troops looted and ransacked the countryside without the 1800 French and Breton soldiers of Laon preventing them to do so.[8] Then, the army headed to Soissons, closely followed by about 2400 men led by Philip of Burgundy, who applied the strategy of avoiding pitched battles: his men ordered the civilians to take refuge inside cities, got the livestock safe, left a garrison inside each fortification and destroyed the bridges in order to hinder and to guide their enemies.

Anecdotally, the land of Coucy was spared: its lord Enguerrand VII de Coucy, married to Isabella of England, eldest daughter of Edward III, did his best to maintain a cautious neutrality.[9]

On 9 September 1373, on the contrary, the French attacked at Oulchy an isolated English corps, killing its captain Walter Hewitt and numerous men, and capturing several knights and squires, of which Thomas Despenser, brother of the Constable of England himself. But no other incident disturbed the first part of the chevauchée: the English closed ranks and the French followed the instructions of Charles V.[8]

Gradually the French troops, taken by surprise by the landing at Calais, were growing stronger: from Harfleur, the Duke Philip of Orléans was coming with the army of the sea.[3]

While John of Gaunt and John of Brittany were invading the Champagne province, burning Vertus, looting and ravaging Hermonville, Ville-Dommange, Le Meix-Tiercelin, Margerie, Epernay and the countryside around Châlons-en-Champagne,[10] Du Guesclin was heading East, via Paris where he talked with the king. Consequently, when the English arrived before Troyes, around September 22, Du Guesclin, Olivier de Clisson, Louis II of Bourbon, the Duke of Burgundy and more than 7,000 men in garrison had been waiting for them for a week.[11] The position was kea: it prevented any English attempt to march on Paris through Gâtinais, as Edward III in his chevauchée of 1359 or to march on Brittany, as Robert Knolles in his chevauchée of 1370.[3] The English left, around September 25. Froissart writes:[12]

This is how the Duke of Lancaster and the Duke of Brittany rode in the kingdom of France, and led their men ; never did they find anyone to talk to in matter of battle [...] ; they often sent their heralds to the lords who were pursuing them, looking for battle [...] ; but never did the French want to accept.

The two Dukes then went up the Seine, finding a way around the end of September at Gyé-sur-Seine, then heading south to Nivernais.[3]

The French were following the advance of their enemy, in two columns marching in parallel, one on their right flank, the other on their left flank, away of an hour of march from each other. They spent each night in castles or fortified cities, when they English were compelled to bivouacking.[12]

La Mal Coiffée, remnants of the walls (14th c.) of Moulins

Around October 10, the chevauchée crossed the Loire river at the bridge of Marcigny, leaving behind in Charolais a devastated path. The crossing of the Allier river proved more dangerous, and John of Gaunt was forced to go North West towards Moulins where the old bridge stone was one of the rare ways to cross the river. He was almost captured: Louis I of Bourbon was himself in Souvigny on the western bank, and his garrison was stationed at Moulins. Coming from the south-east, Bertrand du Guesclin was tracking down the English, while on October 18, Philip of Burgundy had taken position at the south-west at Saint-Pourçain-sur-Sioule, after he had crossed the Loire at Roanne. Finally, the king had urgently called back from Brittany his brother the Duke of Anjou, who was converging north towards the town with his infantry and archers corps.[3] The English narrowly escaped, but they had to abandon plenty of supply wagons.

And the situation got worse at the approach of winter and a poorer countryside: Auvergne, Limousin, Rouergue, Agenais. At the beginning of November, the French lightened their presence: Louis of Anjou went back to Languedoc, Philip of Burgundy disbanded his mercenaries and rejoined his duchy, the infantry of the North returned to its garrisons. The Marshal of Sancerre took the lead of the operations.

In Combrailles and Upper Limousin, John of Gaunt's soldiers found themselves in one of the most inhospitable regions of France in winter: the dense forest, glacial and almost uninhabited doesn't offer more resources for the horses than for the men ; the cold and torrential rain turns the roads into swamps, filling the streams with a muddy water. The horsemen of Sancerre harassed the flanks of the column, and the English left behind them a long trail of horses, dead of starvation.[3]

Finally, at the beginning of December 1373, the Duke of Lancaster arrived in the valley of the Corrèze river in Lower Limousin, a region still hostile to the authority of the king of France. He was able to rest there three weeks.