The Kingdom of Jerusalem, also known as the Crusader Kingdom, was one of the Crusader states established in the Levant immediately after the First Crusade. It lasted for almost 200 years, from the accession of Godfrey of Bouillon in 1099 until the fall of Acre in 1291. Its history is divided into two periods with a brief interruption in its existence, beginning with its collapse after the siege of Jerusalem in 1187 and its restoration after the Third Crusade in 1192.
The original kingdom lasted from 1099 to 1187 before being almost entirely overrun by the Ayyubid Sultanate under Saladin. Following the Third Crusade, it was re-established in Acre in 1192.