Moulin was eventually captured, and died under brutal torture by the Gestapo, possibly by Klaus Barbie himself. The resistance intensified after it became clear the tide of war had shifted after the Reich's defeat at Stalingrad in early 1943 and, by 1944, large remote areas were out of the German military's control and free zones for the "maquisards", so-called after the maquis shrubland that provided ideal terrain for guerrilla warfare.