The terrritories lost by Germany after the 2nd World War, and where Germans were a minority further east & northeast, are where all of my ancestors hail from.

The first Trunz received his landgrant from Hermann von Salza, the Grandmaster of the Teutonic Knights, in the early part of the 13th century. From the family homestead you could see the church, which amazingly survived the Soviet whirlwind of '45. There's several pictures on the ostpreussen website. A Trunz has been at almost every major battle fought by Prussia through its long history. This branch of the family has significant Polish and Lithuanian blood. My grandfather spoke fluent Polish, as well as Russian...and English.

Bergstrom/Brieg originally hailed from a Swedish enclave (Eastern Bothnia) in Finland, and had some German blood also. Settling in Brieg during the 30 years was when King Gustavus Adolphus lead a Swedish army in that war through the Holy Roman Empire.

Jews that spoke german, from Mitau. One of the two Jews to win the Knight's Cross in the 1st World War, is my namesake- Kurt Wolff. My paternal grandmother was his younger sister. This branch became Prussian soldiers during the time of Fredrick the Great, who was the 1st monarch to emancipate the serfs, and opened the army and civil service to Jews, with a forbear joining up and first fighting at the Battle of Mollwitz in 1741.

https://en.wikipedia.org/wiki/Kurt_Wolff_(aviator)

No wonder i ended up on this side of the Atlantic!