'Siegfried' (ii) was the German original designation of the trio of summer offensives of 1942 on the Eastern Front, later retitled 'Blau I', 'Blau II' and 'Blau III' (28 June/November 1942).

As originally schemed by the Oberkommando des Heeres at the direct instigation of Adolf Hitler, 'Siegfried' (ii) was intended to clear the Soviet forces from the area lying to the west of the Don river, establish powerful strategic defences along the Don river itself between Voronezh and Stalingrad, and take the north-western part of the Caucasus as far to the east as the Manych river (including the oilfields at Maykop), together with the passes over the Caucasus mountains which would make possible a subsequent advance to the southern oilfields at Grozny and Baku.