In the Medieval Period the English Channel was an especially perilous stretch of water. It had two distinct (and often conflicting) functions. It was a rich commercial seaway, on which the rising economy of the known world depended. At the same time it was a wide, lawless, political frontier between two belligerent monarchies, whose kings encouraged piracy as a cheap alternative to warfare, and enjoyed their own cut. Pirates prospered. They stole ships and cargoes, at sea or in port. They raided other ports and carried out long-lasting vendettas against other groups. They ransomed the richest of their captives, but tipped innumerable sailors overboard. This revealing new book explores medieval piracy as it waxed and waned. Dramatic life-stories are set against the better-known landmarks of history. While kings were ambivalent, foreign relations were imperilled, and although it was briefly quelled by Henry V, piracy was never defeated during this turbulent epoch.