Why did Edward III’s early campaigns in France leave him deeply in debt?

Edward III’s early campaigns in France left him deeply in debt primarily because the nature of military recruitment had shifted, making the war an exceptionally expensive endeavor. Unlike earlier periods, Edward’s armies were no longer raised through traditional feudal obligations; instead, they were formed by contract, requiring the king to pay wages to all who fought, in addition to providing them with a share of the profits from campaigning.1

By 1339, Edward found himself in a financial crisis, owing an estimated £300,000. To fund these mounting costs, he had borrowed recklessly from English, Italian, and Flemish bankers and merchants, and he had also seized wool exports to generate revenue. Despite receiving generous grants from Parliament starting in 1336, these funds were insufficient to cover the immense expenses of the conflict, leading to a significant domestic political crisis in 1340–1341.2