This museum traces the history of the city's doomed uprising against the German occupation of the city in 1944. This ended with the German's destruction of the city. The Germans destroyed 80%-90% of the buildings in Warsaw while an immense part of the cultural heritage was deliberately demolished, burned to the ground, or stolen. Currently, more than half of the antiques and museum objects of Polish heritage stolen by Germans in 1944 have not been returned to Poland.Destruction of Warsaw was planned before its final destruction in 1944 and even before the start of World War II.In December 1939, the first mass shootings of civilians took place in the Kampinos Forest near Warsaw, where thousands were killed by 1943. In 1940, round-ups (łapanki) of civilians on streets and in homes became the norm. Those who did not manage to escape were sent to concentration camps at Auschwitz and Majdanek or forced into slave labour in Germany. The Nazis divided Warsaw into a Jewish sector, a Polish sector and a German sector. The programme of annihilation and ethnic cleansing was systematically carried out starting with Polish Jews and Jews from other areas shipped into the Warsaw ghetto.By 1944 around 800,000 civilians were killed, or 60% of the population.