The Teutonic Knights is a Roman Catholic military order. It was formed at the end of the 12th century in Acre, Palestine, during the Crusades. The Teutonic Knights are now a clerical order based in Vienna, Austria.
In 1226 Konrad of Masovia brought the Teutonic Knights to fight against pagan Prussia. They won quickly, and knights started to be a danger for the then weak Poland. Finally, the power of the Teutonic Order was crushed in Battle of Tannenberg in 1410.