Emperor Showa's 63-year reign from 1926 to 1989 was the longest in Japanese history. The first 20 years of the reign of Hirohito (as he was known during his life) saw the rise of extreme nationalism, racial discrimination against other Asians and a series of wars. During the 1930s, the military took control of the government, ending democracy in Japan. The first part of the Showa era ended in Japan's catastrophic defeat in World War II and its occupation by foreign powers for the first time in its history. But in the later Showa era, the postwar period, Japan re-emerged as a liberal democracy and a major world economic power.

Invasion of Manchuria

Since the end of the Russo-Japanese War, the Liaodong Peninsula in Manchuria had been a leased territory of Japan. But Japan's presence in the region was threatened by the growing power of Chiang Kai-shek, who had formed the Nationalist government of the Republic of China in 1928. Extremists in the Japanese military argued that full control of Manchuria would be in the best interests of Japan. In September 1931, they acted—without permission from the Japanese government.
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In what is known as the Mukden Incident, Japanese army officers bombed a part of the South Manchuria Railway, then falsely accused the Chinese of carrying out the attack. The Kwantung Army (Japanese forces already stationed in Manchuria), swiftly conquered the entire Manchuria region by February 1932 and set up the puppet government (one subject to the orders of the Japanese military) of Manchukuo there.

Japanese forces captured the capital of Nanjing in December and carried out the Nanjing Massacre, today considered one of the worst wartime atrocities in history. Bolstered by assistance from the Soviet Union, the Chinese fought back. After the Japanese army had seized most of China's important cities, including Shanghai, Nanjing, Beijing and Wuhan, the war then descended into a bloody stalemate. This lasted until 1945.

The United States opposed Japan's invasion of China and imposed economic sanctions. Japan then joined an alliance with Nazi Germany and Italy—already engaged in the attempted conquest of Europe during World War II—in September 1940, forming the Tripartite Pact. Japan now had ambitions for the creation of what it termed a Greater East Asian Co-Prosperity Sphere—really a Japanese Empire incorporating much of East and Southeast Asia.

Japanese troops invaded French Indochina, completing the conquest by July 1941. Japan now set its sights on the Dutch East Indies and its valuable oil resources, which Japan needed to fuel its military vehicles and ships. The US tightened economic sanctions on Japan even more.
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Led by its new Prime Minister Hideki Tojo, Japan decided to respond to the US with force. On 7th December 1941 the Japanese Navy launched a surprise attack on the American fleet at Pearl Harbor, Hawaii. This brought the US into World War II on the side of the Allies. But with the main American battle fleet disabled, Japan made rapid advances, overrunning the Dutch East Indies, the Philippines, Malaya, Burma and Singapore in the next 90 days.
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The tide began to turn against Japan following the Battle of Midway in June 1942 and the subsequent Battle of Guadalcanal, in which Allied troops took back the Solomon Islands from Japanese control. During this period, the Japanese military was responsible for war crimes such as mistreatment of prisoners of war and the massacres of civilians.

​​​​​​​In 1944, US forces began bombing raids on Japan itself, wreaking destruction of its major cities. In a desperate response, the Japanese Navy started using squadrons of kamikaze pilots who deliberately crashed their planes into enemy ships.

An Allied victory in the bloody Battle of Okinawa, fought between April and June 1945, was to be the first stage in a planned invasion of Japan. Instead, on 6th August, the US dropped an atomic bomb over Hiroshima, killing over 70,000 people. On 9th August the Soviet Union declared war on Japan and invaded Manchuria. Nagasaki was struck by a second atomic bomb, killing around 40,000 people. With his country facing inevitable defeat, Emperor Hirohito announced Japan's surrender on 15th August 1945.

Allied occupation

The Allies occupied Japan from 1945 unti 1952. US General Douglas MacArthur, the Supreme Commander of Allied Powers, served as Japan's leader. He played a central role in bringing in reforms modelled on the New Deal piloted by US President Franklin D. Roosevelt in the 1930s. A new constitution was enacted in 1947 that transformed Japan into a constitutional monarchy and the parliamentary democracy it is today.

Economic miracle

From around 1955 onwards, with the Liberal Democratic Party in government Japan enjoyed very high economic growth and became one of the world's leading economic powers. During this period, Japan became the world's largest manufacturer of vehicles and a leading producer of electronics. Ordinary Japanese people became wealthier, life expectancy rose and Japan's population increased to 123 million by 1990. It was described as Japan's economic miracle.

Since 1990, the economy has slowed significantly, leading to what some call the "Lost Decades". While still a wealthy nation, Japan's economic growth rate has fallen well below that of many other industrialized nations.
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