Crusader–Fatimid wars: The fortress of Ascalon was surrendered by Fatimid Egypt to an army of crusaders, Templars, and Hospitallers led by King Baldwin III of Jerusalem.

The military history of the Crusader states begins with the formation of the County of Edessa in 1097 and ends with the loss of Ruad in 1302, the last Christian stronghold in the Holy Land.

Ascalon or Ashkelon was an ancient Near East port city on the Mediterranean coast of the southern Levant of high historical and archaeological significance. Its remains are located in the archaeological site of Tel Ashkelon, within the city limits of the modern Israeli city of Ashkelon. Traces of settlement exist from the 3rd millennium BCE, with evidence of city fortifications emerging in the Middle Bronze Age. During the Late Bronze Age, it was integrated into the Egyptian Empire, before becoming one of the five cities of the Philistine pentapolis following the migration of the Sea Peoples. The city was later destroyed by the Babylonians but was subsequently rebuilt.

The siege of Ascalon took place from 25 January to 22 August 1153, in the time period between the Second and Third Crusades, and resulted in the capture of the Fatimid Egyptian fortress by the Kingdom of Jerusalem. Ascalon was an important castle that was used by the Fatimids to launch raids into the Crusader kingdom's territory, and by 1153 it was the last coastal city in Palestine that was not controlled by the Crusaders.

The Fatimid Caliphate, also known as the Fatimid Empire, was a caliphate extant from the tenth to the twelfth centuries CE under the rule of the Fatimids, an Isma'ili Shi'a dynasty. Spanning a large area of North Africa and West Asia, it ranged from the western Mediterranean in the west to the Red Sea in the east. The Fatimids traced their ancestry to the Islamic prophet Muhammad's daughter Fatima and her husband Ali, the first Shi'a imam. The Fatimids were acknowledged as the rightful imams by different Isma'ili communities as well as by denominations in many other Muslim lands and adjacent regions. Originating during the Abbasid Caliphate, the Fatimids initially conquered Ifriqiya. They extended their rule across the Mediterranean coast and ultimately made Egypt the center of the caliphate. At its height, the caliphate included—in addition to Egypt—varying areas of the Maghreb, Sicily, the Levant, and the Hejaz.