Originally Posted by Krusader
About Teutonic Knights. They were predominately Germans, and the vast majority came from modern-day Germany. Foreign nobles were allowed to join, like King Henry IV I believe, who served in the Order for some time, but it was a German Order.
Prussia in the 13th century was inhabited by the Prusiskai tribe, who were pagans. They were defeated and then subjugated by the Order, and numerous German settlers were then sent to the Order's lands to settle and christianize it. Most of the 14th century Prussians served the Order as levy troops.