Origins of the Teutonic Order date back to 1190 in Acre, Kingdom of Jerusalem as hospitallers to aid Christians on their way to pilgrimage in the Holy Land. At first they were a small gathering of knights and paid mercenaries serving to protect their hospitals established in Acre and as a crusading army later on during their purging of heresy in pagans in the Baltics. Their motto was “Help, Defend, Heal” and they were recognized for wearing white surcoats bearing a black cross. Their armaments would mirror that of the Knights Templar, bearing the best armor and weapons gold could buy. The most notable detail was their great helmet adorned with horns.
Leaving the Holy Land
The Holy Land fell to Muslim control, so the Teutonic Knights were called by King Andrew the II of Hungary. Their base of operations was placed in the Kingdom of Hungary, tasked with defending the kingdom from the encroaching Cumans. Their demands grew too much for the Kingdom of Hungary, so they were expelled and gained the Pope’s approval for sovereignty and became independent in 1225, basing their headquarters in Venice.
Causing Trouble North
Five years later, the Teutonic Order was called upon to aid the duke Konrad I of Masovia for a crusade to expel the pagans from Prussia and bring Christianity to the Baltics. The Knights of the Teutonic order yet again proved too demanding for the Polish hosts; despite, with the aid of the Holy Roman Empire they were successful in purging the land of Prussia from heresy. The old Prussians got slaughtered in the fifty year warring, and those that remained unbaptized were culled, slaughtered and exiled.
As the plague had ravaged the land, the Teutonic Order encouraged immigration from the Germanic peoples from the Holy Roman Empire into Prussia, thus cementing a long lasting line of nobility based on military strength backed up by a splendor of wealth. Their support grew to a degree that the Knights of the Teutonic order became an uncontrollable power in the Baltics, allowing them to fully control the Baltic Sea. With the approval of the Holy Roman Empire an expansion of territory had begun toward Livonia and Lithuania.
Assimilating the Livonian Brotherhood of the Sword into their ranks, they begun warring with the Orthodox kingdom of Kievan Rus, resulting in their disastrous defeat at the Battle of Ice by the hands of prince Alexander Nevsky of Novgorod. Over the next decades they healed their wounds, and begun to subjugate the Curonians and the Semigallians, yet suffered a major defeat by the Semigallians in the Battle of Durbe, which resulted in a wave of rebellions throughout Prussia and Livonia.
They managed to win a crucial victory by lifting the Siege of Konigsberg that lasted from 1262 to 1265, resulting in a turning of the war that allowed them to fully subjugate the Curonians in 1267 and the Semigallians in 1290. Therefore, they quelled the Estonian Rebellion from 1343 to 1345. In 1346 they had purchased the Dutchy of Estonia from Denmark, further increasing their power and control. The Teutonic Order had begun to purge the land of Lithuania from pagans as a form of retaliation as Christendom had lost the Holy Land
With the aim of spreading Christianity to every corner of Europe, they were aided by the kingdoms of England and France, which had sent knights to build their military experience on the battlefield itself. The war itself waged on for nearly 200 years with both banks of the river Neman and twenty castles and fortresses between Seredzius and Jurbarkas being the frontline. That created a wasteland – with the brutality of the war outmatching that of the previous conquest of Prussia. A dispute over ownership of the Dutchy of Pomerelia soon developed into war with the Kingdom of Poland, as both the Margraves of Brandenburg and duke Wladislaw I the Elbow-High claimed the right of succession.
The latter requesting aid from the Teutonic Order marched straight into Danzig and expelled the Brandenburgers in September 1308, but refused to yield the town to the Poles and proceeded to massacre the town’s inhabitants. Following the Treaty of Soldin, the Teutonic Knights purchased the rights of owning the castles of Danzig, Schwetz and Dirchau along with the hinterlands from the Margraves on September 13, 1309. Control over Pomerelia had allowed the State of the Teutonic Order to connect with the Holy Roman Empire, allowing for reinforcements, supplies and trade routes to connect via West Pomerania to Pomeralia and finally to Prussia. The Order as well blocked the access to the Baltic Sea for the Kingdom of Poland. Even though they were allies to the Teutonic Order, ownership for the Dutchy of Pomerelia had made the Poles enemies to the Teutonic Knights, forcing them to persecute and abolish powerful knights of the Order beginning in 1307. Despite, ownership over Pomerelia had allowed the Teutonic Knights to move their headquarters from Venice to Marienburg along with the crusade against the Lithuanians, making the Poles their enemies and receiving legal threats from the Papacy. Additionally, the Papacy forced the Teutonic Order to take the Treaty of Kalisz of 1343, ending open war with the Kingdom of Poland, thus losing some lands while retaining others, most notable of which were Pomerelia and Danzig. With the Grand Duke of Lithuania, Jogalia being baptized and marrying the Polish Queen Jadwiga in 1389, had cemented a long lasting alliance or what would later be known as the Commonwealth of Poland and Lithuania that became a strong opponent to the Teutonic Order.
The Order had reached its height in power and greatest territorial extension in 1407, governing over Prussia, Pomerelia, Samogitia, Courland, Livonia, Estonia, and Gotland. The Teutonic Knights fell in decline after decisively losing the Battle of Grunwald against the combined Polish-Lithuanian army, as Grand Master Ulrich von Jungingen and most of the Teutonic Order’s dignitaries fell upon the battlefield. They sparked infighting for power among the rest due to the imposition of huge taxes upon their subjects. So, after a series of losing events, the State of the Order of the Teutonic Knights was split apart and seeded into different kingdoms and empires, resulting in the Teutonic Order effectively being diminished to that of priesthood.