Eustace the Monk

Eustace the Monk (Old French: Eustache le Moine; c. 1170 – 24 August 1217), born Eustace Busket, was a mercenary and pirate, in the tradition of medieval outlaws. The birthplace of Eustace was not far from Boulogne. A 1243 document mentions a Guillaume le Moine, seigneur de Course, which indicates that the family lived in that vicinity.

Eustace was born a younger son of Baudoin Busket, a lord of the county of Boulogne. According to his biography, he went to Toledo, Spain, and studied black magic there. The author of the Histoire des Ducs de Normandie wrote in Eustace's own day, "No one would believe the marvels he accomplished, nor those which happened to him many times." He later returned home to become a Benedictine monk at St Samer Abbey near Calais, and then left the monastery to avenge his murdered father. Other evidence, however, suggests that his father's death occurred soon after 1190. That evidence proves that by 1202, Eustace was the seneschal and bailiff of the count of Boulogne, Renaud de Dammartin, and that in c. 1204, the two quarrelled and, accused of mishandling his stewardship, Eustace fled and was declared an outlaw. Renaud confiscated his lands and fields; Eustace burned two mills in retaliation.

Eustace became a pirate in the English Channel and the Strait of Dover, both for his own purposes and as a mercenary of France and England. King John of England employed him intermittently from 1205 to 1212, against Philip II of France. The biography asserts that John gave him command of thirty ships at the start of this assignment. This employment involved Eustace and his brothers raiding the Normandy coast and establishing bases in the Channel Islands (he and his men held Castle Cornet in Guernsey for a considerable period). He took the island of Sark in 1205. When he raided English coastal villages, King John briefly outlawed him, but soon afterwards issued a pardon because he needed Eustace's services.

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