World War II: Nazi Germany starts its strategic summer offensive against the Soviet Union, codenamed Case Blue.
Case Blue (German: Fall Blau) was the German Armed Forces' name for its plan for the 1942 strategic summer offensive in southern Russia between 28 June and 24 November 1942, during World War II. The objective was to capture the oil fields of Baku (Azerbaijan SSR), Grozny and Maikop for two purposes: to enable the Germans to re-supply their low fuel stock and also to deny their use to the Soviet Union, thereby bringing about the complete collapse of the Soviet war effort.
After Operation Barbarossa failed to destroy the Soviet Union as a political and military threat the previous year, Adolf Hitler, the Fhrer of Nazi Germany, recognised that Germany was now locked in a war of attrition, and he was also aware that Germany was running low on fuel supply and would not be able to continue attacking deeper into enemy territory without more stock. With this in mind, Hitler ordered for the preparation of offensive plans for summer 1942 to secure the Soviet oil fields in the Caucasus. The operation involved a two-pronged attack: one from the Axis right flank against the oil fields of Baku, known as Operation Edelweiss, and one from the left flank to protect the first attack, moving in the direction of Stalingrad along the Don River, known as Operation Fischreiher.Army Group South (Heeresgruppe Sd) of the German Army was divided into Army Groups A and B (Heeresgruppe A and B). Army Group A was tasked with fulfilling Operation Edelweiss by crossing the Caucasus mountains to reach the Baku oil fields, while Army Group B protected its flanks along the Volga by fulfilling Operation Fischreiher.
Supported by 2,035 Luftwaffe aircraft and 1,934 tanks and assault guns, the 1,570,287-man Army Group South began the offensive on 28 June, advancing 48 kilometers on the first day and easily brushing aside the 1,715,000 Red Army troops opposite, who falsely expected a German offensive on Moscow even after Blau commenced. The Soviet collapse in the south allowed the Germans to capture the western part of Voronezh on 6 July and reach and cross the Don river near Stalingrad on 26 July. Army Group B's approach toward Stalingrad slowed in late July and early August owing to constant counterattacks by newly deployed Red Army reserves and overstretched German supply lines. The Germans defeated the Soviets in the Battle of Kalach and the combat shifted to the city itself in late August. Nonstop Luftwaffe airstrikes, artillery fire and street-to-street combat completely destroyed the city and inflicted heavy casualties on the opposing forces. After three months of battle, the Germans controlled 90% of Stalingrad on 19 November.
In the south, Army Group A captured Rostov on 23 July and swept south from the Don to the Caucasus, capturing the demolished oilfields at Maikop on 9 August and Elista on 13 August near the Caspian Sea coast. Heavy Soviet resistance and the long distances from Axis sources of supply reduced the Axis offensive to local advances only and prevented the Germans from completing their strategic objective of capturing the main Caucasus oilfield at Baku. Luftwaffe bombers destroyed the oilfields at Grozny but attacks on Baku were prevented by the insufficient range of the German fighters.
The Allies were concerned about the possibility of German forces continuing to the south and east and linking up with Japanese forces (then advancing in Burma) in India. However, the Red Army defeated the Germans at Stalingrad, following Operations Uranus and Little Saturn. This defeat forced the Axis to retreat from the Caucasus in order to avoid getting cut off by the Red Army, which was now advancing from Stalingrad down towards Rostov in order to achieve the cut-off. Only the Kuban region remained tentatively occupied by Axis troops.
World War II or the Second World War, often abbreviated as WWII or WW2, was a global war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. In a total war directly involving more than 100 million personnel from more than 30 countries, the major participants threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and the only two uses of nuclear weapons in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, a majority being civilians. Tens of millions of people died due to genocides (including the Holocaust), starvation, massacres, and disease. In the wake of the Axis defeat, Germany and Japan were occupied, and war crimes tribunals were conducted against German and Japanese leaders.
The exact causes of World War II are debated, but contributing factors included the Second Italo-Ethiopian War, the Spanish Civil War, the Second Sino-Japanese War, the Soviet–Japanese border conflicts and rising European tensions since World War I. World War II is generally considered to have begun on 1 September 1939, when Nazi Germany, under Adolf Hitler, invaded Poland. The United Kingdom and France subsequently declared war on Germany on 3 September. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union had partitioned Poland and marked out their "spheres of influence" across Finland, Estonia, Latvia, Lithuania and Romania. From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, and formed the Axis alliance with Italy and Japan (along with other countries later on). Following the onset of campaigns in North Africa and East Africa, and the fall of France in mid-1940, the war continued primarily between the European Axis powers and the British Empire, with war in the Balkans, the aerial Battle of Britain, the Blitz of the UK, and the Battle of the Atlantic. On 22 June 1941, Germany led the European Axis powers in an invasion of the Soviet Union, opening the Eastern Front, the largest land theatre of war in history.
Japan, which aimed to dominate Asia and the Pacific, was at war with the Republic of China by 1937. In December 1941, Japan attacked American and British territories with near-simultaneous offensives against Southeast Asia and the Central Pacific, including an attack on the US fleet at Pearl Harbor which resulted in the United States declaring war against Japan. Therefore the European Axis powers declared war on the United States in solidarity. Japan soon captured much of the western Pacific, but its advances were halted in 1942 after losing the critical Battle of Midway; later, Germany and Italy were defeated in North Africa and at Stalingrad in the Soviet Union. Key setbacks in 1943—including a series of German defeats on the Eastern Front, the Allied invasions of Sicily and the Italian mainland, and Allied offensives in the Pacific—cost the Axis powers their initiative and forced it into strategic retreat on all fronts. In 1944, the Western Allies invaded German-occupied France, while the Soviet Union regained its territorial losses and turned towards Germany and its allies. During 1944 and 1945, Japan suffered reversals in mainland Asia, while the Allies crippled the Japanese Navy and captured key western Pacific islands.
The war in Europe concluded with the liberation of German-occupied territories, and the invasion of Germany by the Western Allies and the Soviet Union, culminating in the fall of Berlin to Soviet troops, Hitler's suicide and the German unconditional surrender on 8 May 1945. Following the Potsdam Declaration by the Allies on 26 July 1945 and the refusal of Japan to surrender on its terms, the United States dropped the first atomic bombs on the Japanese cities of Hiroshima, on 6 August, and Nagasaki, on 9 August. Faced with an imminent invasion of the Japanese archipelago, the possibility of additional atomic bombings, and the Soviet’s declared entry into the war against Japan on the eve of invading Manchuria, Japan announced on 15 August its intention to surrender, then signed the surrender document on 2 September 1945, cementing total victory in Asia for the Allies.
World War II changed the political alignment and social structure of the globe. The United Nations (UN) was established to foster international co-operation and prevent future conflicts, with the victorious great powers—China, France, the Soviet Union, the United Kingdom, and the United States—becoming the permanent members of its Security Council. The Soviet Union and the United States emerged as rival superpowers, setting the stage for the nearly half-century-long Cold War. In the wake of European devastation, the influence of its great powers waned, triggering the decolonisation of Africa and Asia. Most countries whose industries had been damaged moved towards economic recovery and expansion. Political and economic integration, especially in Europe, began as an effort to forestall future hostilities, end pre-war enmities and forge a sense of common identity.