A privateer who continued raiding after the expiration of a commission or the signing of a peace treaty could face accusations of piracy. Depending on the specific sovereign and the time period, commissions might be issued hastily privateers might take actions beyond what was authorized in the commission, including after its expiry. The commission usually protected privateers from accusations of piracy, but in practice the historical legality and status of privateers could be vague. However, this incentive increased the risk of privateers turning to piracy when war ended. For participants, privateering provided the potential for a greater income and profit than obtainable as a merchant seafarer or fisher. Privateering allowed sovereigns to raise revenue for war by mobilizing privately owned armed ships and sailors to supplement state power. A percentage share usually went to the issuer of the commission (i.e. Captured ships were subject to condemnation and sale under prize law, with the proceeds divided by percentage between the privateer's sponsors, shipowners, captains and crew. This included attacking foreign vessels and taking them as prizes and taking crews prisoner for exchange. The commission empowered the holder to carry on all forms of hostility permissible at sea by the usages of war. A sovereign or delegated authority issued commissions, also referred to as letters of marque, during wartime.

Since robbery under arms was a common aspect of seaborne trade, until the early 19th century all merchant ships carried arms. Person or ship engaging in maritime warfare under commission East Indiaman Kent (left) battling Confiance, a privateer commanded by French corsair Robert Surcouf in October 1800, as depicted in a painting by Ambroise Louis Garneray.Ī privateer is a private person or vessel that engages in maritime warfare under a commission of war.

Us navy ships war of 1812