The murder of thousands of Polish officers and representatives of the elite by the Soviets was a planned action of extermination of that part of the society of the Second Republic, which formed the foundation of Polish statehood. For the Communists, it was a prelude to their subsequent seizure of power, which is why the Katyn lie became one of the cornerstones of the Polish People's Republic. From the beginning, however, Poles demanded that the truth about the crime be revealed.