The provincial capital was Oppeln (1919–1938) and Kattowitz (1941–1945), while other major towns included Beuthen, Gleiwitz, Hindenburg O.S., Neiße, Ratibor and Auschwitz, added in 1941 (the place of future extermination of Jews in World War II).

Large demographic changes took place between 1819 and 1910, with the region's total population quadrupling, the percent of German-speakers increasing significantly, and that of Polish-speakers declining considerably.

[5] Polish authors before 1918 estimated the number of ethnic Poles in Prussian Upper Silesia as slightly higher than according to figures from official German censuses.

Among other stipulations, according to the treaty each contractual party guaranteed in its respective part of Upper Silesia equal civil rights for all the inhabitants.

The first conference of the Nazi anti-Polish organization Bund Deutscher Osten in Upper Silesia was held on 9 June 1933 in Gliwice.

[14] A secret Sicherheitsdienst report from 1934, mentioned Bytom, Gliwice, Prudnik, Strzelce Opolskie, Zabrze and the Olesno and Opole rural districts as the main centers of the Polish movement in the province.

German occupation forces began a policy of repression against the Polish population of eastern Upper Silesia, which started as early as September 1939[18] based on lists made before the war that pointed out Poles active in social and political life.

[18] A second wave of arrests happened during October and November in Intelligenzaktion Schlesien, aimed against Polish intellectuals, many of whom perished in prison camps.

In Katowice, according to the historian Czesław Madajczyk, one of the harshests centres of oppression was the prison on Mikołowska street where people were reported to be murdered by Germans through the use of guillotine.

In case of children born between September 1939 and December 1950, their origin was reported based on the pre-war places of residence of their mothers.