Hello,
I noticed your posting. I am Lithuanian on my father's side and East Prussian on my maternal grandfather's side, so I have been researching this area for some time. Vistytis is SW Lithuania, in a border region.
East Prussia was a depopulated country in 1708 due to the plague. In 1732, Frederck I, King of Prussia and a protestant, used the expulsion of protestants from Salzburg, Austria in 1731 to repopulate Prussia. One account I read stated that 17,000 protestants from Salzburg ended up in Prussia which became known as the "protector of all protestants". Interestingly, my maternal grandfather's surname is DAVID and our family's oral history says they were originally French (protestants) from eastern France who settled in Koenigsburg.
Also, I learned that I am connected to the exulants of Salzburg on my mother's mother's father's line from Bavaria. Through YDNA testing, it was discovered that this line is Haplogroup T. That was my first indication that my ancestors were from Tyrol. Further investigation revealed that my great great grandfather was indeed protestant who converted to marry. After speaking with cousins in Germany, they expressed that they believed that our ancestral line was from Salzburg originally who settled in the area of Nuremberg, one of the stopping off places for refugees headed for Prussia.
Have you considered DNA testing?
Carol