World War II

• 1. Introduction

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  World War II killed between 60 and 75 million people, making it the deadliest conflict in history. Tanks and aircraft reshaped the battlefield, and aircraft carried out the strategic bombing of cities. Aircraft also delivered the only nuclear weapons ever used in war. Nearly every country on Earth took part, split between two coalitions: the Allies and the Axis powers. The fighting ran from the 1st of September 1939 to the 2nd of September 1945. Millions died not in battle but from massacres, starvation, disease, and genocides, including the Holocaust. How did a single global conflict pull in almost the whole world, and why do historians still argue over the day it truly began? What turned grievances left over from one war into the machinery of an even larger one? And how did the victory remake the political map for the rest of the century?

• 2. Disputed Beginnings

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  Most historians fix the start of World War II at the 1st of September 1939, when Nazi Germany invaded Poland. Britain and France declared war on Germany two days later. Yet the date is far from settled, and the disagreement reveals how many fuses were already burning.

  The Pacific War has its own contested origins. Some scholars date it to the Second Sino-Japanese War, which broke out on the 7th of July 1937. Others reach back further, to Japan's invasion of Manchuria on the 18th of September 1931.

  Antony Beevor, a British historian, places the war's beginning at the Battles of Khalkhin Gol, fought between Japan and the forces of Mongolia and the Soviet Union from May to September 1939. Still others propose the Italian invasion of Abyssinia on the 3rd of October 1935, or treat the Spanish Civil War as the war's prelude.

  The ending resists agreement too. At the time, people marked the close of the war with the armistice of the 15th of August 1945, known as V-J Day, rather than Japan's formal surrender on the 2nd of September. A peace treaty between Japan and the Allies was not signed until 1951. Japan and the Soviet Union never signed a formal peace treaty at all, ending their state of war only through the Soviet-Japanese Joint Declaration of 1956.

• 3. The Shadow Of Versailles

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  The Treaty of Versailles stripped Germany of around 13 percent of its home territory and all its overseas possessions. It barred Germany from annexing other states, imposed reparations, and limited the size and capability of its armed forces. These losses fed a bitter revanchist nationalism, especially sharp in Germany.

  The League of Nations, founded in 1920 by the Paris Peace Conference, was meant to prevent another world war through collective security and disarmament. It would prove unable to do so. When Italy invaded Ethiopia, both nations belonged to the League, yet it did little as Italy violated Article X of its Covenant.

  Benito Mussolini's fascist movement seized power in Italy between 1922 and 1925, abolishing representative democracy and promising a "New Roman Empire". Mussolini repressed socialist, left-wing, and liberal forces and pursued an aggressive expansionist foreign policy.

  Adolf Hitler became chancellor of Germany in 1933, appointed by President Paul von Hindenburg and the Reichstag, after his 1923 attempt to overthrow the government had failed. The Nazis quickly abolished parliamentary democracy and launched a massive rearmament campaign. When Hindenburg died in 1934, Hitler proclaimed himself Führer of Germany.

• 4. Appeasement And Its Limits

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  In March 1936, Hitler remilitarised the Rhineland in defiance of the Versailles and Locarno Treaties, meeting little opposition thanks to the policy of appeasement. In October of that year, Germany and Italy formed the Rome-Berlin Axis. A month later, Germany and Japan signed the Anti-Comintern Pact, which Italy joined the following year.

  The Munich Agreement handed Germany the Sudetenland, an area of Czechoslovakia with a predominantly ethnic German population. British Prime Minister Neville Chamberlain conceded the territory against the wishes of the Czechoslovak government, in exchange for a promise of no further demands. Soon after, Germany and Italy forced Czechoslovakia to cede territory to Hungary, and Poland annexed the Trans-Olza region.

  In March 1939, Germany invaded the remainder of Czechoslovakia, splitting it into the Protectorate of Bohemia and Moravia and the pro-German Slovak Republic. Hitler then issued an ultimatum to Lithuania on the 20th of March 1939, forcing the concession of the Klaipeda Region. After demands over the Free City of Danzig and the Polish corridor, Britain and France guaranteed Polish independence.

  On the 23rd of August 1939, the Soviet Union signed a non-aggression pact with Germany. Its secret protocol divided spheres of influence: Lithuania for Germany, and Finland, Estonia, Latvia, and Bessarabia for the Soviet Union, with Poland to be partitioned between the two. The pact ensured Germany would not face a Soviet war when it invaded Poland.

• 5. Proxy Wars In Spain And China

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  More than 70,000 Italian ground troops, 6,000 aviation personnel, and 720 aircraft were sent by Mussolini to support the Nationalist rebels in the Spanish Civil War, led by General Francisco Franco. Italy backed the Nationalists more heavily than the Nazis did. The Soviet Union supported the existing government of the Spanish Republic, and more than 30,000 foreign volunteers, the International Brigades, fought against the Nationalists. Both Germany and the Soviet Union used this proxy war to test their most advanced weapons and tactics in combat.

  Franco's Nationalists won in April 1939. As dictator, Franco stayed officially neutral during World War II but generally favoured the Axis, his largest collaboration being the sending of volunteers to fight on the Eastern Front.

  In July 1937, Japan captured the former Chinese imperial capital of Peking after instigating the Marco Polo Bridge incident. Generalissimo Chiang Kai-shek deployed his best army to defend Shanghai, but the city fell after three months of heavy fighting. The Japanese captured the capital, Nanking, in December 1937.

  Chinese forces stalled the Japanese advance in June 1938 by flooding the Yellow River, buying time to prepare defences at Wuhan, though that city fell by October. The Chinese government relocated inland to Chongqing and kept fighting. Japanese aircraft began striking cities in the Sichuan basin, killing tens of thousands of civilians in a campaign meant to break Chinese morale.

• 6. Barbarossa And The Eastern Front

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  On the 22nd of June 1941, Germany invaded the Soviet Union in Operation Barbarossa, supported by Italy and Romania and soon joined by Finland and Hungary. The surprise offensive aimed at the Baltic region, Moscow, and Ukraine, with the goal of reaching the Arkhangelsk-Astrakhan line by the end of the year. Hitler's objectives were to destroy the Soviet Union as a military power, exterminate communism, and seize Lebensraum, or living space, by dispossessing the native population.

  Nazi policy subjected Soviet prisoners of war to murderous treatment. The Commissar Order required executing all Jewish and Communist prisoners immediately, while the rest were forced into open-air camps and deliberately starved. By the end of the winter of 1941, 2.8 million Soviet prisoners had died in German captivity. By the war's end, some 3.3 million had died, a mortality rate near 60 percent.

  German troops almost reached the outer suburbs of Moscow before exhaustion forced them to halt. The campaign failed its main objectives: two key cities stayed in Soviet hands, and Soviet resistance was not broken. The blitzkrieg phase of the war in Europe had ended.

  On the 5th of December 1941, freshly mobilised Soviet reserves launched a massive counter-offensive that pushed German troops 100 to 250 kilometres west. Intelligence showing that few Soviet troops were needed in the East to deter the Japanese Kwantung Army had freed up these forces.

• 7. The Pacific Turns

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  On the 7th of December 1941, Japan attacked British and American holdings with near-simultaneous offensives across Southeast Asia and the Central Pacific. These included strikes on the American fleets at Pearl Harbor and the Philippines, and invasions of Guam, Wake Island, Malaya, Thailand, and Hong Kong. The attacks brought the United States, the United Kingdom, China, Australia, and other states into formal war against Japan. Germany and the other Axis states then declared war on the United States.

  After capturing Bataan, Japanese armies forced some 75,000 Filipino and American prisoners onto a 42-kilometre death march that killed thousands. Japanese advances came with numerous atrocities, including the Sook Ching Massacre in Singapore.

  The tide turned at Midway. The Americans had broken Japanese naval codes in late May 1942 and knew the plans and order of battle. They used this knowledge to win a decisive victory over the Imperial Japanese Navy in early June, gutting Japan's capacity for aggressive action.

  Guadalcanal became a focal point for both sides, with heavy commitments of troops and ships. Japanese forces suffered massive losses in the attrition, especially among their elite pilots. By the start of 1943, the Japanese were defeated on the island and withdrew their troops.

• 8. Surrender And A New Order

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  On the 30th of April 1945, Hitler killed himself in his headquarters, and the Reichstag was captured the same day, signalling the military defeat of Nazi Germany. Benito Mussolini had been killed by Italian partisans two days earlier. Total and unconditional surrender in Europe was signed on the 7th and the 8th of May, to take effect by the end of the 8th of May 1945.

  A devastating raid on Tokyo on the 9th and the 10th of March 1945 was the deadliest conventional bombing raid in history. In early August, the United States dropped atomic bombs on Hiroshima and Nagasaki. Between the two bombings, the Soviets declared war on Japan, invaded Japanese-held Manchuria, and quickly defeated the Kwantung Army, the largest Japanese fighting force.

  Emperor Hirohito ordered his cabinet to accept Allied terms on the night of the 9th to the 10th of August 1945. On the 15th of August he announced the decision to the Japanese people in a radio broadcast. Japan surrendered, and the surrender documents were signed at Tokyo Bay aboard an American battleship on the 2nd of September 1945.

  The war remade the world's political, economic, and social structures. The United Nations was created, with 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 Cold War. As Europe's great powers waned, decolonisation swept across Africa and Asia.