Somme (river) invasion fleet of William the Conqueror assembled in the Bay of the Somme, at Saint-Valery-sur-Somme. The river also featured in the 1346 withdrawal of Edward III of England's army, which forded the river at the Battle of Blanchetaque during the campaign, which culminated in the Battle of Crécy. Crossing the river also featured prominently in the campaign which led to the Battle of Agincourt in 1415. In 1636, a Spanish army led by Thomas Francis, prince of Carignan, crossed the Somme defeating a French army during the Thirty Years War threatening Paris. Most famously, the Battle of the Somme, during
Battle of Agincourt an army about three times the size of their own fighting force". It is open to debate whether these should all be counted as non-combatants; Rogers (for example) accepts that the French probably had about 10,000 men-at-arms, but explicitly includes one "gros valet" (an armed, armoured and mounted military servant) per French man-at-arms in his calculation of the odds. Soon after the English victory at Agincourt, a number of popular folk songs were created about the battle, the most famous being the "Agincourt Carol", produced in the first half of the 15th century. Other ballads followed, including "King Henry Fifth's