Ordo domus Sanctae Mariae Theutonicorum, Deutscher Orden, the Teutonic Knights or the Teutonic Order was first formed under Roman Rite Catholicism in Palestine in the 12th century by Papal Decree to take Jerusalem for Christianity and to give medical aid to pilgrims.
After an unsuccessful campaign to secure Jerusalem the Teutonic Order moved north, initially to Venice. Though they were no longer crusading in Judea, the leaders thought to instigate crusades against the pagan nations. The Knights posed as religious mercenaries and offered their services to Christian Kings. It was their hope that they would be able to use their influnce in The Holy Roman Empire to acquire these formerly pagan lands for themselves.
First accepted in Austria by Andrew II of the Magyars, the Order was given a district in Burzenland, Transylvania, though this was later recanted when the Order sought to have direct relation with the Holy See and not through the Kingdom of Hungary.
This proved somewhat fortuitous for the Order, as they were freed to renew their conquest under direction of Konrad I Mazowiecki, Prince of Culmland (Central Veneda) when his homeland was attacked by the Prussians, a pagan Baltic people.
This led the Order to rule a large tract of the Eastern Baltic, though this power had eroded by the end of the middle ages. The Order quickly fell out of political life and sought to serve as a more religious organization.