page_title: Henry of Grosmont, 1st Duke of Lancaster
section_title: 1345
hierarchical_section_title: Henry of Grosmont, 1st Duke of Lancaster / Adult career / North-east France / 1345
context_page_description: Henry of Grosmont, 1st Duke of Lancaster, 4th Earl of Leicester and Lancaster, Earl of Derby KG, of Bolingbroke Castle in Lincolnshire, was a member of the English royal family and a prominent English diplomat, politician, and soldier. He was the wealthiest and most powerful peer of the realm. The son and heir of Henry, 3rd Earl of Lancaster, and Maud Chaworth, he became one of King Edward III's most trusted captains in the early phases of the Hundred Years' War and distinguished himself with victory in the Battle of Auberoche. He was a founding member and the second Knight of the Order of the Garter in 1348, and in 1351 was created Duke of Lancaster. An intelligent and reflective man, Grosmont taught himself to write and was the author of the book Livre de seyntz medicines, a highly personal devotional treatise. He is remembered as one of the founders and early patrons of Corpus Christi College, Cambridge, which was established by two guilds of the town in 1352.
context_section_description: Edward III determined early in 1345 to attack France on three fronts. The Earl of Northampton would lead a small force to Brittany, a slightly larger force would proceed to Gascony under the command of Grosmont, and the main force would accompany Edward to either northern France or Flanders. Grosmont was appointed the King's Lieutenant in Gascony on 13 March 1345 and received a contract to raise a force of 2,000 men in England, and further troops in Gascony itself. The highly detailed contract of indenture had a term of six months from the opening of the campaign in Gascony, with an option for Edward to extend it for a further six months on the same terms. Derby was given a high degree of autonomy, for example his strategic instructions were: "si guerre soit, et a faire le bien q'il poet" (... if there is war, do the best you can ...).
  On 9 August 1345 Grosmont arrived in Bordeaux with 500 men-at-arms, 1,500 English and Welsh archers, 500 of them mounted on ponies to increase their mobility, and ancillary and support troops. Rather than continue the cautious war of sieges he was determined to strike directly at the French before they could concentrate their forces. He decided to strike at the French at Bergerac, which had good river supply links to Bordeaux, and would provide the Anglo-Gascon army with a base from which to carry the war to the French and sever communications between French forces north and south of the Dordogne. After eight years of defensive warfare by the Anglo-Gascons, there was no expectation among the French that they might make any offensive moves. Grosmont moved rapidly and took the French army at Bergerac by surprise on 26 August, decisively beating them in a running battle.  French casualties were heavy, many being killed or captured. Derby's share of the ransoms and the loot was estimated at £34,000 (£33,000,000 in 2020 terms), approximately four times the annual income from his lands. 
  Grosmont left a large garrison in the town and moved north with 6,000–8,000 men to Périgueux, the provincial capital of Périgord, which Grosmont blockaded, taking several strongholds on the main routes into the city. John, Duke of Normandy, the son and heir of Philip VI, gathered an army reportedly numbering over 20,000 and manoeuvred in the area. In early October a very large detachment relieved the city and drove off Grosmont's force and started besieging the English-held strongpoints. A French force of 7,000 besieged the castle of Auberoche, 9 miles (14 km) east of Périgueux. A messenger got through to Grosmont, who was already returning to the area with a scratch force of 1,200 English and Gascon soldiers: 400 men-at-arms and 800 mounted archers.
  After a night march Grosmont attacked the French camp on 21 October while they were at dinner, taking them by surprise. There was a protracted hand-to-hand struggle, which ended when the commander of the small English garrison in the castle sortied and fell upon the rear of the French. They broke and fled. Derby's mounted men-at-arms pursued them relentlessly. French casualties are uncertain, but were heavy. They are described by modern historians as "appalling", "extremely high", "staggering", and "heavy". Many French nobles were taken prisoner; lower ranking men were, as was customary, put to the sword. The ransoms alone made a fortune for many of the soldiers in Grosmont's army, as well as Grosmont himself, who was said to have made at least £50,000 (£49,000,000 in 2020 terms) from the day's captives.
caption: August–November 1345 troop movements  Derby's advance  Derby's retreat  Louis of Poitiers' advance  Derby's advance to Auberoche  Derby's return to La Réole