The pirate hanged in Boston in 1704 after the capture of the brigantine Charles was John Quelch.
John Quelch was an English pirate who began his career as an officer aboard the Charles, a vessel commissioned from Boston to privateer against French ships during the War of the Spanish Succession. Instead, Quelch and his crew mutinied and sailed south, where they attacked Portuguese ships and took valuable cargo.
Portugal was then allied with England, so the attacks were treated as piracy rather than lawful privateering. The crew returned to the American colonies, but their sudden wealth attracted suspicion. Authorities arrested Quelch and several associates, and he was tried under colonial maritime law.
Quelch was convicted and executed in Boston in 1704. His case is significant because it was the first admiralty trial held in the Massachusetts Bay Colony. It also shows why a privateering commission did not authorize attacks on every ship a crew encountered.