 In 1942 , members of the British Parliament characterised the campaign in Greece as a " political and sentimental decision " . Eden rejected the criticism and argued that the UK 's decision was unanimous and asserted that the Battle of Greece delayed Operation Barbarossa , the Axis invasion of the Soviet Union . This is an argument that historians such as Keegan used to assert that Greek resistance was a turning point in World War II . According to film @-@ maker and friend of Adolf Hitler Leni Riefenstahl , Hitler said that " if the Italians hadn 't attacked Greece and needed our help , the war would have taken a different course . We could have anticipated the Russian cold by weeks and conquered Leningrad and Moscow . There would have been no Stalingrad " . Despite his reservations , Brooke seems also to have conceded that the Balkan Campaign delayed the offensive against the Soviet Union . 
