Siege of Calais (1436)

The Siege of Calais between June and July 1436 was a failed siege of English-held Calais by Philip the Good, Duke of Burgundy and Flemish militia.

England and Burgundy had been allies against France in the Hundred Years' War since 1415.
But when the English walked out of peace talks during the Congress of Arras in 1435, the Duke of Burgundy stayed and concluded the Treaty of Arras with the French King, thus switching sides in the war. The English were outraged because of the Duke's betrayal, and the London populace was allowed the plunder possessions of Flemish, Dutch and Picard merchants in the city, all subjects of the Duke of Burgundy. There was also an incursion in the Duke's territories by an English force of 2000 men, who defeated 1500 Flemish soldiers under Jean II de Croÿ in the Boulonnais.

Philip the Good reacted by declaring war on England. In this, he was supported by the Flemish cities, who saw their trade with England menaced.

The obvious target of the Duke was Calais. He first conquered some smaller English strongholds, like Oye castle, where he hanged part of the garrison, Sangatte and Balinghem. In June he started the siege of Calais, supported by large numbers of Flemish and Picard militia. The Flemish cities in fact saw a chance to deal with the Calais Staple. In total, the Duke had some 30,000 men at his disposal. He also sent a force under Jean II de Croÿ to besiege Guînes.

The militia had been very eager to take Calais quickly, but when after a few weeks it became apparent that the city, under the command of Edmund Beaufort, 2nd Duke of Somerset, was well defended and provisioned, the enthusiasm quickly decreased. When a fleet under Admiral John of Horne failed to block the harbor of Calais by sinking five to six ships laden with stone, the Flemish army started to disintegrate.

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