Following the joint German-Soviet invasion of Poland, which started World War II in September 1939, the town was occupied by Germany until 1945. In September 1939, the German "Einsatzgruppe I" entered the town to commit various atrocities against the population. Nearly all of Czeladź' Jewish community was murdered during the occupation. Jews numbered around 1,000, about 5% of the population, at the beginning of the war. The German invasion led to the immediate abuse, robbery, and murder of Jewish residents. 22 Polish policemen and 15 Polish military officers from Czeladź were murdered by the Russians in the large Katyn massacre in April–May 1940. In June 1940, both Poles and Polish Jews were forced to go to the town square where they were beaten and tortured as retaliation for the murder of a German. Police and Gestapo beat the prisoners in an orgy of violence that lasted all day as blood ran freely. Afterwards, 20 of the Jews were detained and murdered. Polish hostages from Czeladź were among 20 Poles massacred by the Germans on July 16, 1940, in Olkusz. In 1941, the Germans forced Jews into a ghetto. Periodically, some were sent to forced labor camps. In May 1942, 200 residents of the ghetto were sent to Auschwitz. Most sent to Auschwitz were immediately murdered or died later from starvation, disease, and brutality. In May, 1943, the ghetto was "liquidated" with the last Jews sent to Będzin and then on to Auschwitz. Only 40 Czeladź Jews are thought to have survived Auschwitz, the labor camps, or by hiding in the area. The Germans also established and operated three forced labor subcamps (E580, E587, E754) of the &lt;a href="Stalag%20VIII-B"&gt;Stalag VIII-B/344&lt;/a&gt; prisoner-of-war camp in the town. In 1944, the Germans sent kidnapped Polish children from Czeladź to the Potulice concentration camp.