Quartermaster, XVII century
The term Quartermaster in the past indicated a specific naval rank that in modern time has been substituted by Helmsman.
Among pirates the Quartermaster's authority was second to only that of the Captain. The rule was that during battle the Captain retained unlimited authority, but at all other times he and the rest og the crew were subject to the command of the Quartermaste. Often when a ship was captured the Quartermaster took over has the Captain of it till decision was madewhelter unrig or not.