The Germania Knights are the Strike Witches' version of the Teutonic Knights, with a different origin and purpose than what they did in the real world as Christianity doesn't exist in the SW universe, it is an important organization in the world.
They were created in 1190 by the Holy Karlsland Empire as a way to carry on with the Western Roman Empire's tradition of having an elite force of warriors and witches to deal with threats to the Empire.
The moment to prove their worth came in the year of 1240 when the Great Mongolian Empire came to invade Europe and they were tasked with defending the land of Poland, Grandmaster of the order at the moment, Gehard von Malberg led the knights against the Mongols in their first incursion, while they were able to halt the advance of the Mongols, the order received a massive blow and the daughter of the Grandmaster and a Karlslander witch, Mila was captured by the Mongols.
Mila lived with the Mongols for a year where she learned their ways and managed to reach a deeper connection with her familiar becoming one of the most powerful European witches in recorded history, her healing powers became so strong she was able to grow limbs back. She was released after a year and was appointed grandmaster of the order replacing her father and tasked to march against the Mongols again which she reluctantly did so.
The battle however was interrupted when a group of Rästel (Neuroi) attacked the city of Opole; both armies agreed to cease fire and fought the Rästel in the Battle of Opole, defeating the invading force.
Mila convinced the Mongol commander, Subotai to unite against the Rästel and put an end to this threat, and so The Germania Knights united their forces with the Mongol Empire and together they battled and defeated the Rästel in the Battle of Legnica, the first recorded battle in history where two nations united against the Neuroi.
After this the Germania Knights made a pact with the Mongols managing to make them return to Asia saving Europa, this actions made them gain prestige with the Emperor and they were awarded the state of Prussia where Mila took the order and settled there.
This state would eventually become the Kingdom of Prussia which would eventually took over and unite the land creating the Karlsland Empire in 1871.
The order still exist today and Karlsland witches who become heroes and perform valiant and incredible actions for the land are knighted into the order, the greatest honor a witch can receive in the Karlsland Empire.
Strike Witches is property of Humikane.