Immediately after the German army occupied Hungary on March 19, the Germans took rapid organizational action to annihilate Hungarian Jewry, the largest Jewish community in Europe that had not yet been swept away for genocide. In short order, from the first deportation on May 15 until the transports were halted on July 7, 437,000 persons were deported and a large majority of them met their deaths in the gas chambers of Auschwitz-Birkenau, to which they were sent directly upon arrival at the camp. The others were put to work in Auschwitz, its sub-camps, and various other Nazi camps. Out of the more than 800,000 Jews in Greater Hungary (as defined by the Hungarian racial definition), nearly 570,000 were murdered.