During the Crusades, Asqalan (known to the Crusaders as "Ascalon") was an important city due to its location near the coast and between the Crusader States and Egypt. In 1099, shortly after the Siege of Jerusalem, a Fatimid army that had been sent to relieve Jerusalem was defeated by a Crusader force at the Battle of Ascalon. The city itself was not captured by the Crusaders because of internal disputes among their leaders. This battle is widely considered to have signified the end of the First Crusade. As a result of military reinforcements from Egypt and a large influx of refugees from areas conquered by the Crusaders, Asqalan became a major Fatimid frontier post. The Fatimids utilized it to launch raids into the Kingdom of Jerusalem. Trade ultimately resumed between Asqalan and Crusader-controlled Jerusalem, though the inhabitants of Asqalan regularly struggled with shortages in food and supplies, necessitating the provision of goods and relief troops to the city from Egypt on several occasions each year. According to William of Tyre, the entire civilian population of the city was included in the Fatimid army registers. The Crusaders' capture of the port city of Tyre in 1134 and their construction of a ring of fortresses around the city to neutralize its threat to Jerusalem strategically weakened Asqalan. In 1150 the Fatimids fortified the city with fifty-three towers, as it was their most important frontier fortress. Three years later, after a seven-month siege, the city was captured by a Crusader army led by King Baldwin III of Jerusalem. The Fatimids secured the head of Husayn from its mausoleum in the city and transported it to their capital Cairo. Ascalon was then added to the County of Jaffa to form the County of Jaffa and Ascalon, which became one of the four major seigneuries of the Kingdom of Jerusalem.