The activities of the Order among the Crusader Kingdom of Jerusalem contributed greatly to the establishment of its military and administrative institutions, and a center for the study of doctrines of fortification and fortification which later contributed to the development and intensification of the Order throughout Europe. The main outpost of the order was the Monfort Fortress, which also served as its headquarters in the 13th century. 

More About The Teutonic Order

Furthermore, the Teutonic Order took an active part in the fighting events in the Frankish East and in the historical events that took place in the Crusader kingdom. In the first half of the 13th century, the Order took part in the Fifth Crusade (1217-1221) and the conquest of Damietta in Egypt and gained much recognition and appreciation for its military capability and determination on the battlefield.

Also in 1228, the Teutonic Order accompanied the journey of Emperor Frederick II to the east, and in 1229 stood by him at the signing of the Treaty of War in Jaffa with the Egyptian Sultan al-Kamel and even attended his coronation ceremony for King of Jerusalem in the Church of the Holy Sepulcher. The fighters of the order fought at the Battle of Gaza in 1239, at the Battle of Hiribya in 1244; and also accompanied the voyages of King Louis IX of France in Egypt in 1249 and of the English Prince Edward of the Galilee in 1271. On that year, July 4, they lost their main stronghold. Monfort Fortress, which was conquered by the Mamluk Sultan Baibars. 

Lastly, known Fortresses and churches in the Land of Israel belonging to them are the Monfort; Yehiam Fortress; King’s Fortress (Mi’ilya), and Church of Mary of the Germans in Jerusalem.