By the end of World War II the number of Romanian prisoners of war in the Soviet Union was significant, about 140,000 of them having been taken prisoner even after August 23, 1944, the date when Romania switched its alliance from the Axis Powers to the Allies. These prisoners of war worked in various labor camps. Some were originally from Bessarabia and Northern Bukovina[citation needed], which were occupied by the Soviet Union in 1940, some were from Romania proper.