Finally, what happened to them when the Crusader States we’re finally conquered? Did any move to Europe?
I answered a similar question recently:
What was the social standing of oriental christians in the crusader states of the levant?
To summarize: Eastern Christians had a pretty high social standing, they intermarried with the crusaders frequently, and they often served in the military, as doctors, as merchants, and could become quite wealthy and prestigious.
I don't know if any of them moved to Europe after 1291, but eastern Christians were also prominent on crusader Cyprus in the 13th and 14th centuries.