Where did the Crusaders go after 1291?

First, it should be noted that there were a lot of Eastern Christians in the Middle East before during and after the Crusades. Some of their cultural descendents still live in Lebanon and Israel/Palestine and Iraq and Syria. There are many Christians in Egypt.

If you're talking about Western colonists and their descendents, they almost certainly were all expelled by the Mameluke rulers of Egypt in the late 13th century. The famous general and Sultan Baybars did his best to erase all traces of Christian domination and he was followed by other Mamelukes who had the same policy. Experts on the Crusades basically think that Muslim rulers of Egypt and the Levant got tired of repeated invasions and did their best to make it impossible for Western Christians to establish themselves on the coast.

Cyprus remained under the rule of a French dynasty for a longer time, but eventually they went too leaving behind the much longer established Greek Christians who are still there.

Question: Where did the Crusaders go after 1291?

Short Answer:
In 1291 Europeans lost their last major stronghold in the Holylands. Europeans could generally choose between converting to Islam, leaving, or death ( not arguing their weren't exceptions). However that wasn't the end of the Crusades. The Crusades ended in 1271, and what happened in 1291 the fall of the Kingdom of Jerusalem was the result.

Detailed Answer:
The Crusades were seasonal and ended in 1271 not 1291. The Crusades were typically done in response to Papal calls to arms. Crusades had a beginning and an end even if individual Crusades lasted for years, they always ended. Crusaders were like militant tourists, looking to have their tickets punched. Looking to do their bit, and go home. Thus the period of the Crusades (1096 and 1271) was actually a series of 9 different crusades.

• First Crusade: 1096 - 1099 - The People's Crusade - Freeing the Holy Lands. led by Count Raymond IV of Toulouse and proclaimed by many wandering preachers, notably Peter the Hermit
• Second Crusade: 1144 -1155 - Crusaders prepared to attack Damascus. led by Holy Roman Emperor Conrad III and by King Louis VII of France
• Third Crusade: 1187 -1192 - led by Richard the Lionheart of England, Philip II of France, and Holy Roman Emperor Frederick I. Richard I made a truce with Saladin
• Fourth Crusade: 1202 -1204 - led by Fulk of Neuil French/Flemish advanced on Constantinople The Children's Crusade: 1212 - led by a French peasant boy, Stephen of Cloyes
• Fifth Crusade: 1217 - 1221 - led by King Andrew II of Hungary, Duke Leopold VI of Austria, John of Brienne
• Sixth Crusade: 1228 - 1229 - led by Holy Roman Emperor Frederick II
• Seventh Crusade: 1248 - 1254 - led by Louis IX of France
• Eighth Crusade: 1270 - led by Louis IX
• Ninth Crusade: 1271 - 1272 - led by Prince Edward (later Edward I of England)

1291 is when the last stronghold of the Kingdom of Jerusalem Fell, when Europeans who controlled Jerusalem were given the choice of converting to Islam, leaving or getting killed. Which was kinda a result of the end of the "Crusades". Without the Periodic inflow of new armies, which is what the Crusades were, European influence and military foothold on the ME was destined to collapse.

Why did the Crusades end? No one reason.

• Crusades were never particularly "efficient". No Centralized Leadership, pursued by short lived armies each lead by independently minded knobles who often didn't get along or agree on objectives.
• The Religious fervor which fueled the Crusades was hard to maintain across all the instability going on back in Europe. (droughts, disease, wars, political and religious troubles).
• Distance which fed logistical and communication troubles.
• The rise of charismatic Islamic Military Leaders Zengi, Nur al-Din, Saladin who challenged the Europeans. Europe ultimately had to step up or step back.

When Europe's religious fervor began to wane in favor of challenges closer to home they stopped sending new Crusades. Then it was only a matter of time before the infrastructure ( kingdoms and Castles ) which there to enable and safeguard the pilgrims, fell.

A large portion of the (ex-)Crusaders married local Christian women and stayed behind in the Levant after the demise of the Crusader states. The largest Christian community in present-day Palestine are the Latin-rite Catholics, generally believed to be descendants of Crusaders, though now they speak Arabic and are integrated in Palestinian society.

Quoted from "The Civilization of the Middle Ages" by Norman F. Cantor:

"Indeed, Acre never fell to the Moslems. In 1291 the French knights who garrisoned it decided that their homeland had forgotten them and that the siege of many years to which they had been subjected would never be relieved. They arranged with the Arab general to surrender the castle and left with their honor intact and their crucifix-laden pennants flying high."

It appears that the crusaders were eventually pushed back onto Cyprus, which continued to have Frankish rulers for another three centuries.

The Knights Hospitaller also moved on to Rhodes for about two centuries, until expelled by Suleiman. From there they moved to Malta, which they held until Napoleon took it from them in 1798.

The Knights Templar tried to maintain a base on a small island off the coast of Syria, but were overrun by the Mamluks in 1303 and never really recovered. The order was dissolved by the Pope in 1307.