When Margaret's embassies all failed, she became an ambassador herself and then an exile. After a year in Scotland following the Lancastrian defeat at the battle of Towton, she and Prince Edward sailed from Kirkcudbright in April 1462. Margaret's eventual purpose was to bargain with Louis XI for aid, but she landed first in Brittany, where she was well received by Duke Francis II, and then went on to meet her father and Pierre de Brezé at Angers in May. After these preliminaries, which may have offered her encouragement and support, she met with King Louis at Chinon in June.

Margaret came as a suppliant; she needed military aid in the form of men and money to continue the fight for the throne. But she also had a bargaining counter that Louis coveted: Calais, whose recovery had been desired by the kings of France ever since its conquest by King Edward III in 1347. Following Charles VII's recovery of Normandy in 1449–50 and of Gascony in 1453, it was the last piece of former French possessions still in England's hands. But Calais and its outpost towers were surrounded by Burgundian, not French, territory, so access for a French attack required Burgundian cooperation, which had not been forthcoming. Margaret's offer of Calais to King Louis was a desperate gamble, for it was of even more importance to the English than it was to the French. Edward III had granted Calais a monopoly as the wool staple, through which all exports of that precious commodity must pass, paying customs duty to the staplers and to the crown. Psychologically, its importance to the English was incalculable, for it was their last foothold, however tenuous, on French soil.

[115] Queen Margaret to Louis XI of France, 24 June 1462 at Chinon

(Wavrin, Anchiennes Croniques, III, pp. 176–7, from Trésor des Chartes, J 648, n° 2)