The Fall of Outremer
The Rest of Outremer Falls
So Acre fell, in May of 1291. It was by far the strongest city, and the greater part of the Kingdom's strength had perished there. No one gave much consideration of defending anywhere else. Tyre capitulated the very next day. Sidon surrendered 14 July and Haifa on 30 July. Tortosa, the last town of any significance, surrendered on 3 August. The very last outpost on the mainland was the castle of Athlit, which surrendered on 14 August.
The Templars retreated to a castle on the little island of Ruad, where they held out for another decade. But the island had no fresh water, and the cost of maintaining the outpost grew too great. It was abandoned in 1303.
Yes, there was much talk back in Europe. There were more crusades proclaimed. But no actual forces would be sent until the 1330s. The ideal of recovering Jerusalem was still strong in Christendom. As the Ottoman Turks grew in strength, focus shifted more in the direction of countering their expansion in eastern Europe, and there were major expeditions mounted in 1391 and 1444. They ended in disaster.
The last crusade in my own estimation is that preached by Pope Pius II in 1464, a reaction to the capture of Constantinople by the Turks. He preached the crusade and received promises of troops and money, but no actual action. With response embarassingly limp, he decided to lead the crusade himself, even though he was ill. The story goes that his advisors had the windows of his litter drawn closed as he approached Ancona so that he could not see that no one at all had come. It seems a fitting if poignant end to the narrative.