This admittedly might just be an incorrect perception, but I've recently been reading a few books on the crusades. I keep getting the feeling that they treat the Ordensstaat as this unique political identity that is defined by a crusading force holding political power over a region without being beholden to a sovereign ruler. But, I'm struggling to understand why this is any different than other Crusader holdings in Malta or Rhodes. I remember my undergrad crusade class emphasizing that, even in kingdoms where the crusaders technically served at behest of the king, they often had defacto rule over their territories.
Any idea why this distinction has emerged?
Originally when it was founded, the Teutonic Order's founding papal letter was heavily drawn from previous and similar papal letters granted to the Knights Templar (Omne datum optimum, 1139) and the Knights Hospitaller (Christianae fidei religio, 1154). Since they were military orders created to serve the papacy they were explicitely forbidden to be infeodated to temporal powers and they were allowed to keep for themselves the plunder acquired from non-Christian ransacked towns and fortresses. Likewise they were exempted to answer to bishops. Nevertheless, they could have churches, priests and cemeteries of their own.
It led to funny quarrels within bishoprics when the Teutonic Knights received the right to bury lay men: bishops would have those corpses dug out, stolen and brought back to their own cemeteries. Pope Innocent III actually had to formally forbid those macabre disputes.
Herman von Salza was the leading figure who carved the Teutonic Order into what it'd become later. He was close to both the emperor (Frederick II) and the pope (Honorius III) and spent time at the Roman Curia to insure the Teutonic Order received all the priviledges it needed to function independantly. From January 9th to February 9th 1221, he secured no less than 34 papal letters at the benefit of the Teutonic Order! That's more than one a day--and they say the papal administration runs slow!
Honorius III was the most generous with the Teutonic Order. His letter Effectum iusta (1216) not only confirmed the temporal and spiritual autonomy of the Teutonic Orders, but it also granted them the right to create villages, build church and dig cemeteries in any location given to them. They basically got a free-pass at colonizing any given land and they were free to manage those lands as they saw fit with no temporal or spiritual supervision. They were still answering to the pope, of course, but he basically let them run free.
Those priviledges proved much valuable to the Teutonic Knights in the Holy Land since they had just purchased "Château du Roi", a fiefdom formerly owned by Jocelin III de Courtenay. They could do with it as they pleased and they would do the same, later on, in Prussia.
Honorius III also passed another great charter, Esti neque (1220), only a few years later. The Teutonic Knights are now seen as a proper crusading order, funded and centred on the Holy Land like the Knights Templar and the Knights Hospitaller. They can even now create villages, build churches and dig cemetaries in lands considered as "desert" (however, the concept of "desert" is very wide and large in the central and late Middle Ages as studies on the cistercian order have found).
The Teutonic Knights fought to archive and maintain their numerous priviledges. They kept their close political connexions to the pope and the emperor much alive throughout the Middle Ages. However, it is only when they acquired Prussia and split it from the Polish realm that they laid the bases for a properly independant state. Gregory IX placed Prussia directly under pontifical jurisdiction (1234) and explicitely forbade any temporal or spiritual lord to claim any authority upon those lands. None of the other crusading orders ever managed to get such a priviledge. They were lords in their own lands alright, but those lands always came with strings attached. The crusading orders couldn't be infeodated to temporal or spiritual lords, sure, but the lands they ruled were effectively under the jurisdiction of such lords for the land, in and of itself, was what granted anyone their nobility.
It meant that the Knights Templar, for example, couldn't become servants to the king of France as such, but the lands they had acquired in France sure depended from French lords or the king himself.
Before they got their hands on Prussia, the Teutonic Knights had quite a little venture in Hungary (1211-1225) that proved to them why a total political autonomy was paramount. They'd been called upon by King Andrew II of Hungary to settle in a "desert land", the Burzenland, that was actually occupied by Szekelys and Vlachs. They slowly acquired more and more priviledges such as building wooden fortresses. Nonetheless the Teutonic Knights build their fortresses in stone. In 1223, they were being exempted from the authority of the bishop of Transylvania. The latter went "What?" and rallied the Hungarian nobility against the Teutonic Knights. A war broke out. As it turns out, Andrew II also had his own priviledges acquired from the Roman Curia. It had been stated that his son could recover any land previously granted. Moreover the Teutonic Knights had minted their own coins and that only constituted a crime against the regal authority. They were therefore booted out of the kingdom.
The Teutonic Order wasn't a souvereign faction from the get go. However, they quickly understood why a total political independance from temporal and spiritual lords was most important if they were to achieve their goals. They first acquired scattered lands all over the Holy Roman Empire and the Holy Land, whether they'd been invited to settle upon some "desert" and colonize it or they'd been able to purchase a fiefdom. Called upon by the king of Poland to recover the rebellious Pomerania, they conquered it for themselves and created the sovereign principality of Prussia with the political backing of the papacy. Whereas the Knights Templar were faced with the growing central power of the French monarchy, which ultimately resulted in their doom (1312), the Teutonic Knights flourished within the dicentralized regions of the Holy Roman Empire and their Prussian principality became a major political player East of Europe. Malbork became their proper capital city and the head of a centralized state once the treasure was transfered from the Holy Land in 1309.
I would conclude that the political autonomy of the Teutonic Knights must be evaluated through time, depending on the papal letter their received, for each and everyone of their holdings. Ultimately they birthed a not so short-lived centralized and souvereing state, but we shouldn't consider them as politically independant everywhere, at any point in time, within the time frame of the crusades and the Middle Ages.
Main source: Sylvain Goughenheim, Les Chevalier teutoniques. Paris: Tallandier, 2007.