person held by another as a guarantee that certain actions or promises will or will not be carried out. During periods of internal turmoil, insurgents often seize hostages; recent examples include seizures of Americans and other foreigners by militants in Iran (1979–81) and Lebanon (1980s). Military forces often take hostages among civilians in an occupied country, in order to ensure the delivery of requisitions, to discourage hostile acts, or to take reprisals for hostile acts committed by unknown persons. In World War II, thousands of hostages were executed throughout Europe by the German authorities in an attempt to crush resistance movements. The Geneva Convention of 1949 forbade entirely the taking of civilian hostages. Criminals, especially when confronted by police, sometimes take hostages as "human shields" or as bargaining assets. In 1998 it was revealed that Israel was holding Lebanese hostages solely for use in prisoner exchanges or other deals with Lebanese guerrillas; their detainment was condoned by Israel's supreme court.
Ancient military custom regulated the behavior and treatment of hostages; originally a hostage was a person who had been delivered by one authority to another as a token of good faith, and was generally treated as an honored guest. However, he might be imprisoned or even executed if the agreement guaranteed by his person was broken. The code of honor was often very strictly observed in feudal times; thus, during the Hundred Years War, when the hostages sent to England in exchange for the release of John II of France escaped, King John felt bound to return to captivity in England. Until the 18th cent., hostages were often exchanged when treaties were concluded.