Letters of Marque and Reprisal documents are written permissions, which gave their owners authority to capture or destroy property belonging to a certain group or nation.
The governments usually issued letters of Marque . When it was necessary, person, who operated under a Letters of Marque and Reprisal, was treated as regular national army.
Letters of Marque were used mostly by privateers . Especially during the wars, governments authorized many ship owners, to equip it with arms in order to attack enemy war ships and seize merchant shipping. Even during the age of buccaneers, every attack on Spaniards, had to be authorized, with some kind of letter of Marque. However, authenticity of these authorizations was often questionable.
T he first Letter of Marque was issued in 1243 from Henry III of England. Their original function was only for retaliatory purposes, not for declaration of war. Later, they were mostly used during the wartimes in order to get a cheap naval army. Since 16th century, the privateers had to give percentage of captured booty to the government in return for authorization. The use of Letters of Marque has been forbidden since the Declaration of Paris in 1856.