Meanwhile, Alfried was held in Landsberg prison, where Hitler had been imprisoned in 1924. At the Krupp Trial, held in 1947–1948 in Nuremberg following the main Nuremberg trials, Alfried and most of his co-defendants were convicted of crimes against humanity (plunder and slave labor), while being acquitted of crimes against peace, and conspiracy. Alfried was condemned to 12 years in prison and the "forfeiture of all [his] property both real and personal," making him a pauper. Two years later, on 31 January 1951, John J. McCloy, High Commissioner of the American zone of occupation, issued an amnesty to the Krupp defendants. Much of Alfried's industrial empire was restored, but he was forced to transfer some of his fortune to his siblings, and he renounced arms manufacturing.