Operations
Offensive
The initial primary goal of the operation was declared as "to impose upon Russia the will of the United States and the British Empire. Even though 'the will' of these two countries may be defined as no more than a square deal for Poland, that does not necessarily limit the military commitment". [3] (The Soviet Union is referred to as Russia throughout the document, a metonym that was common in the West throughout the Cold War.)
The chiefs of staff were concerned that both the enormous size of the Soviet forces deployed in Europe at the end of the war and the perception that Soviet Premier Joseph Stalin was unreliable caused a Soviet threat to exist in Allied-held Western Europe. The USSR had yet to launch its attack on Japanese forces and so one of the assumptions in the report was that the Soviets would instead ally with Japan if the Western Allies commenced hostilities.
The hypothetical date for the start of the Allied invasion of Soviet-held Eastern Europe was scheduled for 1 July 1945, four days before the United Kingdom general elections. [7] The plan assumed a surprise attack by as many as 47 British and American divisions in the area of Dresden, in the middle of Soviet lines. [7] That represented almost half of the approximately 100 divisions available to the British, American and Canadian headquarters at that time. [8]
The plan was considered by the British Chiefs of Staff Committee as militarily unfeasible due to an anticipated 2.5:1 superiority in divisions of Soviet ground forces within Europe and the Middle East by 1 July, when the conflict was projected to occur. [9] Most of the offensive operation would have been performed by American and British forces, as well as Polish forces and as many as 10 divisions of the German Army, remobilised from prisoner-of-war status. Any quick success would be caused by surprise alone. If a quick success could not be obtained before the beginning of winter, the assessment was that the Allies would be committed to a protracted total war. In the report of 22 May 1945, an offensive operation was deemed "hazardous".
The following table is based on Allied estimates at the time of the planning of Operation Unthinkable.
Defensive
In response to an instruction by Churchill of 10 June 1945, a follow-up report was written on "what measures would be required to ensure the security of the British Isles in the event of war with Russia in the near future". [11] American forces were relocating to the Pacific region for a planned invasion of Japan, and Churchill was concerned that the reduction of forces would give the Soviets a strong advantage for offensive action in Western Europe. The report concluded that if the United States engaged solely in the Pacific Theatre, Britain's odds "would become fanciful". [12]
The Joint Planning Staff rejected Churchill's notion of retaining bridgeheads on the Continent as not having any operational advantage. It was envisaged that Britain would use its air force and navy to resist, but a threat from mass rocket attack was anticipated, with no means of resistance except for strategic bombing.
World War II or the Second World War was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries—including all the great powers—participated, with many investing all available economic, industrial, and scientific capabilities in pursuit of total war, blurring the distinction between military and civilian resources. Tanks and aircraft played major roles, with the latter enabling the strategic bombing of population centres and delivery of the only two nuclear weapons ever used in war. World War II was the deadliest conflict in history, resulting in 70 to 85 million fatalities, more than half of which were civilians. Millions died in genocides, including the Holocaust of European Jews, and by massacres, starvation, and disease. Following the Allied powers' victory, Germany, Austria, Japan, and Korea were occupied, and war crimes tribunals were conducted against German and Japanese leaders.
The Tehran Conference was a strategy meeting of Joseph Stalin, Franklin D. Roosevelt, and Winston Churchill from 28 November to 1 December 1943. It was held at the Soviet Union's embassy at Tehran in Iran. It was the first of the World War II conferences of the "Big Three" Allied leaders and closely followed the Cairo Conference, which had taken place on 22–26 November 1943, and preceded the 1945 Yalta and Potsdam conferences. Although the three leaders arrived with differing objectives, the main outcome of the Tehran Conference was the Western Allies' commitment to open a second front against Nazi Germany. The conference also addressed the Big Three Allies' relations with Turkey and Iran, operations in Yugoslavia and against Japan, and the envisaged postwar settlement. A separate contract signed at the conference pledged the Big Three to recognize Iranian independence.
The Yalta Conference, held 4–11 February 1945, was the World War II meeting of the heads of government of the United States, the United Kingdom and the Soviet Union to discuss the postwar reorganization of Germany and Europe. The three states were represented by President Franklin D. Roosevelt, Prime Minister Winston Churchill, and General Secretary Joseph Stalin. The conference was held near Yalta in Crimea, Soviet Union, within the Livadia, Yusupov, and Vorontsov palaces.
The Cairo Conference, also known as the First Cairo Conference, was one of 14 summit meetings during World War II, which took place on November 22–26, 1943. The Conference was held at Cairo in Egypt between China, the United Kingdom and the United States. Attended by Chairman Chiang Kai-shek, British Prime Minister Winston Churchill and US President Franklin D. Roosevelt, it outlined the Allied position against the Empire of Japan during World War II and made decisions about post-war Asia.
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The final battles of the European theatre of World War II continued after the definitive surrender of Nazi Germany to the Allies, signed by Field marshal Wilhelm Keitel on 8 May 1945 in Karlshorst, Berlin. After German leader Adolf Hitler's suicide and handing over of power to grand admiral Karl Dönitz on the last day of April 1945, Soviet troops conquered Berlin and accepted surrender of the Dönitz-led government. The last battles were fought on the Eastern Front which ended in the total surrender of all of Nazi Germany’s remaining armed forces such as in the Courland Pocket in western Latvia from Army Group Courland in the Baltics surrendering on 10 May 1945 and in Czechoslovakia during the Prague offensive on 11 May 1945.
Operation Sledgehammer was an Allied plan for a cross-Channel invasion of Europe during World War II, as the first step in helping to reduce pressure on the Soviet Red Army by establishing a Second Front. It was to be executed in 1942 and acted as a contingency alternative to Operation Roundup, the original Allied plan for the invasion of Europe in 1943. Allied forces were to seize the French Atlantic ports of either Brest or Cherbourg and areas of the Cotentin Peninsula during the early autumn of 1942, and amass troops for a breakout in the spring of 1943.
The Cold War originated in the breakdown of relations between the two main victors in World War II: United States and the Soviet Union, and their respective allies, the Western Bloc and the Eastern Bloc, in the years 1945–1949.
Europe first, also known as Germany first, was the key element of the grand strategy agreed upon by the United States and the United Kingdom during World War II after the United States joined the war in December 1941. According to this policy, the United States and the United Kingdom would use the preponderance of their resources to subdue Nazi Germany in Europe first. Simultaneously, they would fight a holding action against Japan in the Pacific, using fewer resources. After the defeat of Germany—considered the greatest threat to the UK and the Soviet Union—all Allied forces could be concentrated against Japan.
Western betrayal is the view that the United Kingdom, France, and sometimes the United States failed to meet their legal, diplomatic, military, and moral obligations with respect to the Czechoslovak and Polish states during the prelude to and aftermath of World War II. It also sometimes refers to the treatment of other Central and Eastern European states at the time.
The Combined Chiefs of Staff (CCS) was the supreme military staff for the United States and Britain during World War II. It set all the major policy decisions for the two nations, subject to the approvals of British Prime Minister Winston Churchill and U.S. President Franklin D. Roosevelt.
The Prague offensive was the last major military operation of World War II in Europe. The offensive was fought on the Eastern Front from 6 May to 11 May 1945. Fought concurrently with the Prague uprising, the offensive significantly helped the liberation of Czechoslovakia in 1945. The offensive was one of the last engagements of World War II in Europe and continued after Nazi Germany's unconditional capitulation on 8/9 May.
The Allies, formally referred to as the United Nations from 1942, were an international military coalition formed during World War II (1939–1945) to oppose the Axis powers. Its principal members by the end of 1941 were the "Big Four" – the United Kingdom, United States, Soviet Union, and China.
The Soviet–Japanese War was a campaign of the Second World War that began with the Soviet invasion of Manchuria following the Soviet declaration of war against Japan on 8 August 1945. The Soviet Union and Mongolian People's Republic toppled the Japanese puppet states of Manchukuo in Manchuria and Mengjiang in Inner Mongolia, as well as northern Korea, Karafuto on the island of Sakhalin, and the Kuril Islands. The defeat of Japan's Kwantung Army helped bring about the Japanese surrender and the end of World War II. The Soviet entry into the war was a significant factor in the Japanese government's decision to surrender unconditionally, as it was made apparent that the Soviet Union was not willing to act as a third party in negotiating an end to hostilities on conditional terms.
The percentages agreement was a secret informal agreement between British Prime Minister Winston Churchill and Soviet leader Joseph Stalin during the Fourth Moscow Conference in October 1944. It gave the percentage division of control over Eastern European countries, dividing them into spheres of influence. It is also known as the naughty document, a nickname coined by Churchill himself due to his concerns regarding American reaction to any deal with such strong imperialist undertones, although in reality U.S. President Franklin Roosevelt was consulted tentatively and conceded to the agreement. The content of the agreement was first made public by Churchill in 1953 in the final volume of his memoir. The US ambassador Averell Harriman, who was supposed to represent Roosevelt in these meetings, was excluded from this discussion.
During the early stages of World War II, the United Kingdom and France made a series of proposals to send troops to assist Finland against the Soviet Union during the Winter War, which started on 30 November 1939. The plans involved the transit of British and French troops and equipment through neutral Norway and Sweden. The initial plans were abandoned because Norway and Sweden declined transit through their land for fear that their countries would be drawn into the war. The Moscow Peace Treaty ended the Winter War in March 1940, which precluded the possibility of intervention.
Lieutenant General Sir Geoffrey Stuart Thompson was a senior British Army officer who became Military Secretary.
Operation Jupiter was a plan originating in 1941 for an invasion of northern Norway and Finland by Allied forces during the Second World War. The first versions of the plan were code named Operation Dynamite, Operation Ajax and Operation Marrow. Devised and vigorously promoted by Sir Winston Churchill, the Prime Minister of the United Kingdom, the plan was opposed by all the senior British and Allied commanders, who considered it impractical because of insufficient air support and of limited value. The scheme was eventually abandoned in favour of the Normandy landings.
United States war plans for a conflict with the Soviet Union (USSR) were formulated and revised on a regular basis between 1945 and 1950. Although most were discarded as impractical, they nonetheless would have served as the basis for action had a conflict occurred. At no point was it considered likely that the Soviet Union or United States would resort to war, only that one could potentially occur as a result of a miscalculation. Planning was conducted by agencies of the Joint Chiefs of Staff, in collaboration with planners from the United Kingdom and Canada.
The Cold War from 1947 to 1948 is the period within the Cold War from the Truman Doctrine in 1947 to the incapacitation of the Allied Control Council in 1948. The Cold War emerged in Europe a few years after the successful US–USSR–UK coalition won World War II in Europe, and extended to 1989–1991. It took place worldwide, but it had a partially different timing outside Europe. Some conflicts between the West and the USSR appeared earlier. In 1945–1946 the US and UK strongly protested Soviet political takeover efforts in Eastern Europe and Iran, while the hunt for Soviet spies made the tensions more visible. However, historians emphasize the decisive break between the US–UK and the USSR came in 1947–1948 over such issues as the Truman Doctrine, the Marshall Plan and the breakdown of cooperation in governing occupied Germany by the Allied Control Council. In 1947, Bernard Baruch, the multimillionaire financier and adviser to presidents from Woodrow Wilson to Harry S. Truman, coined the term "Cold War" to describe the increasingly chilly relations between three World War II Allies: the United States and British Empire together with the Soviet Union.
