Siege of Acre
After a siege of nearly two years Acre surrendered once Richard I and Philip II arrived; it then became the capital of the Kingdom of Jerusalem.

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Released after Hattin, Guy of Lusignan was refused entry to Tyre and in August 1189 laid siege to Acre with a small force. Saladin’s army soon encircled the besiegers in turn, and for nearly two years both sides lost many men to hunger and disease.
When Philip II (April) and Richard I (June) arrived in 1191 and battered the walls with siege engines, the garrison surrendered on 12 July. As ransom negotiations dragged on, Richard executed about 2,700 Muslim prisoners in August.