World War II: During the preliminaries of the Battle of Rostov, German forces reach the Sea of Azov with the capture of Mariupol.
The Battle of Rostov (1941) was a battle of the Eastern Front of World War II, fought around Rostov-on-Don between the Army Group South of Nazi Germany and the Southern Front of the Soviet Union.
The battle comprised three phases: the German Sea of Azov Offensive Operation by Army Group South (General Gerd von Rundstedt) (begun on 12 September 1941), the Soviet Rostov Defensive Operation (5 November 1941 – 16 November 1941) by the Southern Front (General Yakov Timofeyevich Cherevichenko), and the Rostov Offensive Operation (27 November 1941 – 2 December 1941) executed by the same Soviet Front.
After forcing their way across the Mius River on 17 November, the German forces captured 10,000 Soviet troops and took Rostov on 21 November. Six days later the Southern Front, reinforced with the newly raised 37th Army, counterattacked from the north and threatened to surround the overstretched German III Motorized Army Corps. Rundstedt then ordered a retreat to the Mius line from Rostov to prevent the encirclement, which prompted Hitler to immediately fire him. Rundstedt's successor Walther von Reichenau confirmed the retreat order with the backing of the Army High Command Chief of Staff Franz Halder and Hitler relented. The Red Army retook Rostov on 28 November. It was the first successful major Soviet counteroffensive of the war.