Despite considerable losses, in early 1942 Germany and its allies stopped a major Soviet offensive in central and southern Russia, keeping most territorial gains they had achieved during the previous year. In May the Germans defeated Soviet offensives in the Kerch Peninsula and at Kharkov, and then launched their main summer offensive against southern Russia in June 1942, to seize the oil fields of the Caucasus and occupy the Kuban steppe, while maintaining positions on the northern and central areas of the front. The Germans split Army Group South into two groups: Army Group A advanced to the lower Don River and struck south-east to the Caucasus, while Army Group B headed towards the Volga River. The Soviets decided to make their stand at Stalingrad on the Volga.