reprisal, in international law, the forcible taking, in time of peace, by one country of the property or territory belonging to another country or to the citizens of the other country, to be held as a pledge or as redress in order to satisfy a claim. A reprisal, technically, is not an act of war, because it is solely in response to conduct that violated international law. When, however, reprisals are taken against a power of equal strength, they may provoke war. The Covenant of the League of Nations and the Charter of the United Nations classify reprisals as acts endangering peace. Modern international law no longer recognizes private reprisal. This was the right of a private person to satisfy a legal claim against an alien by seizing property belonging to a person of the alien's nationality. The authority was contained in a letter of reprisal issued by the sovereign. Private reprisals all but disappeared by 1800, as the central authority of states grew stronger.

marque and reprisal: see privateering.