Akko fell to the Egyptian Mamelukes (freed slaves of Turkish/Circassian origin) in 1291, bringing to an end the Crusader period.
The Crusader period ended in 1303. 
mnli hypothesis: The Crusader period ended in 1303.  premise: Akko fell to the Egyptian Mamelukes (freed slaves of Turkish/Circassian origin) in 1291, bringing to an end the Crusader period.