Privateer

A privateer is a private person or ship that engages in maritime warfare under a commission of war.[1] The commission, also known as a letter of marque, empowers the person to carry on all forms of hostility permissible at sea by the usages of war, including attacking foreign vessels during wartime and taking them as prizes. Historically, captured ships were subject to condemnation and sale under prize law, with the proceeds divided between the privateer sponsors, shipowners, captains and crew. A percentage share usually went to the issuer of the commission. Since robbery under arms was once common to seaborne trade, all merchant ships were already armed. During war, naval resources were auxiliary to operations on land so privateering was a way of subsidizing state power by mobilizing armed ships and sailors.

In practice the legality and status of privateers historically has often been vague. Depending on the specific government and the time period, letters of marque might be issued hastily and/or the privateers might take actions beyond what was authorized by the letters. The privateers themselves were often simply pirates who would take advantage of wars between nations to gain semi-legal status for their enterprises. By the end of the 19th century the practice of issuing letters of marque had fallen out of favor because of the chaos it caused and its role in inadvertently encouraging piracy.