Schlesien as Prussian province in the 19th century had the size of Kentucky (roughly 40,000 square kilometers) and 3.5+ million inhabitants.
There are a couple of notable people with your names of interest, though:
Joseph Ferche, auxiliary bishop of Breslau, born 1888 in Pschow, now Pszów, on the border to Czechia.
Horst Fuhrmann, a historian, born 1926 in Kreuzburg, now Kluczbork, on the eastern border of Upper Silesia.
Those would be the areas I would start looking.
And good luck!