After the invasion of Poland, which started World War II, between 1939 and 1945, it was occupied by Nazi Germany.
Poles were subjected to persecution, murders, deportations to Nazi concentration camps, and expulsions (see Nazi crimes against the Polish nation).

In the first weeks of the occupation, in September 1939, the Germans arrested and imprisoned numerous Poles from the town and the surrounding area.
About 600 Poles were murdered in the nearby forest, and some were deported to concentration camps.

Between November 6 and 22, 1939, the Germans expelled 2,000 Poles, who were first deported to the temporary concentration camp in Wysin, and then to the so-called General Government.
The expulsions continued until March 1944.
Among the expellees was Tomasz Rogala, who returned to Kościerzyna after the war, and in the following decades was commemorated with a monument.
Poles who refused to sign the Volksliste were arrested and tortured by the Gestapo, some were tortured to death, or murdered, while their families were deported to concentration camps.

Despite this, the Poles managed to organize an underground resistance movement, including the Pomeranian Griffin secret military organization.
After World War II the town was restored to Poland.
After the invasion of Poland, which started World War II, between 1939 and 1945, it was occupied by Nazi Germany. Poles were subjected to persecution, murders, deportations to Nazi concentration camps, and expulsions (see Nazi crimes against the Polish nation).
In the first weeks of the occupation, in September 1939, the Germans arrested and imprisoned numerous Poles from the town and the surrounding area. About 600 Poles were murdered in the nearby forest, and some were deported to concentration camps.
Between November 6 and 22, 1939, the Germans expelled 2,000 Poles, who were first deported to the temporary concentration camp in Wysin, and then to the so-called General Government. The expulsions continued until March 1944. Among the expellees was Tomasz Rogala, who returned to Kościerzyna after the war, and in the following decades was commemorated with a monument. Poles who refused to sign the Volksliste were arrested and tortured by the Gestapo, some were tortured to death, or murdered, while their families were deported to concentration camps.
Despite this, the Poles managed to organize an underground resistance movement, including the Pomeranian Griffin secret military organization. After World War II the town was restored to Poland.
Kościerzyna