Silesia is a historical region of Central Europe located mostly in present-day Poland, with parts in the Czech Republic and Germany.
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Germany (Prussia/Silesia).
Silesia is located in Poland, Germany, and the Czech republic. Inhabitands speak the languages of their 3 respective countries.
Silesia is a where not a who. It's a region in central Europe that on modern day maps would be mostly in SW Poland with small parts in Germany and Czech Republic.
Poland as whole has never been 'a part of Germany'. However, the borders of Poland have moved considerably over the centuries. In 1945 large areas of eastern Germany were transferred to Poland - Silesia, most of Pommerania, most of East Prussia and a large part of Brandenburg. The Germans living in these areas were forcibly moved westwards.
Peter Petran was born on February 9, 1912, in Silesia, Germany.
Horst Hawemann was born in 1940, in Glogau, Lower Silesia, Germany.
Helena Uszok was born in 1923, in Upper Silesia, Germany [now Poland].
Norbert Kuchinke was born on January 1, 1940, in Schwarzwaldau, Silesia, Germany.
Alfred Kurella was born on May 2, 1895, in Brieg, Silesia, Germany.
Franciszka Sklorz was born in 1929, in Upper Silesia, Germany [now Poland].