Knights came first.
Knights of the temple
The crusaders
If they had a cross they were likely to be Crusaders
i am not quite sure, but i think they wanted knights
Some were, most were ordinary people.
Such people were called crusaders.
Shanghai Noon came first
I pretty sure it's hospitalers
They weren't actually called knights... they were called Crusaders, but anyways, they simply went to Crusades to help serve their country and religious beliefs.
Jerusalem was the destination of the first two crusaders.
The Crusaders, who were predominantly Christian knights from Western Europe, were the first Christians to fight against Muslims for control of the Holy Land during the Crusades in the 11th to 13th centuries.
In that time if there was a priest he would have tried to help the sick. Most people just died of whatever the problem was. Medical care was non existent.