The Meiji Restoration was a political and social revolution in Japan in 1866-69, which ended the power of the Tokugawa shogun and returned the Emperor to a central position in Japanese politics and culture. It is named for Mutsuhito, the Meiji Emperor, who served as the figurehead for the movement.
Background to the Meiji Restoration:
When Commodore Matthew Perry of the United States steamed in to Edo Bay (Tokyo Bay) in 1853 and demanded that Tokugawa Japan allow foreign powers access to trade, he unwittingly started a chain of events that led to Japan's rise as a modern imperial power.
Japan's political elites realized that the U.S. and other countries were ahead of Japan in terms of military technology, and (quite rightly) felt threatened by western imperialism. After all, mighty Qing China had been brought to its knees by Britain fourteen years earlier in the First Opium War, and would soon lose the Second Opium War as well.
Rather than suffer a similar fate, some of Japan's elites sought to close the doors even tighter against foreign influence, but the more foresighted began to plan a modernization drive. They felt that it was important to have a strong Emperor at the center of Japan's political organization to project Japanese power and fend off western imperialism.
The Satsuma/Choshu Alliance:
In 1866, the daimyo of two south Japanese domains - Saigo Takamori of Satsuma Domain and Kido Takayoshi of Choshu Domain - formed an alliance against the Tokugawa Shogunate that had ruled from Tokyo in the Emperor's name since 1603. The Satsuma and Choshu leaders sought to overthrow the Tokugawa shogun and place the Emperor Komei into a position of real power. Through him, they felt that they could more effectively meet the foreign threat. However, Komei died in January 1867, and his teenaged son Mutsuhito ascended to the throne as the Meiji Emperor on February 3, 1867.
On November 19, 1867, Tokugawa Yoshinobu resigned his post as the fifteenth Tokugawa shogun. His resignation officially transferred power to the young emperor, but the shogun wouldn't give up actual control of Japan so easily. When Meiji (coached by the Satsuma and Choshu lords) issued an imperial decree dissolving the house of Tokugawa, the shogun had no choice but to resort to arms. He sent his samurai army toward the imperial city of Kyoto, intending to capture or depose the emperor.
The Boshin War
On January 27, 1868, Yoshinobu's troops clashed with samurai from the Satsuma/Choshu alliance; the four-day long Battle of Toba-Fushimi ended in a serious defeat for the bakufu, and touched off the Boshin War (literally, the "Year of the Dragon War"). The war lasted until May of 1869, but the emperor's troops with their more modern weaponry and tactics had the upper hand from the start.
Tokugawa Yoshinobu surrendered to the emperor, and handed over Edo Castle on April 11, 1869. Some of the more committed samurai and daimyo fought on for another month from strongholds in the far north of the country, but it was clear that the Meiji Restoration was unstoppable.
Radical Changes of the Meiji Era
Once his power was secure, the Meiji Emperor (or more precisely, his advisors among the former daimyo and the oligarchs) set about refashioning Japan into a powerful modern nation. They abolished the four-tiered class structure; established a modern conscript army that used western-style uniforms, weapons and tactics in place of the samurai; ordered universal elementary education for boys and girls; and set out to improve manufacturing in Japan, which had been based on textiles and other such goods, shifting instead to heavy machinery and weapons manufacturing. In 1889, the emperor issued the Meiji Constitution, which made Japan into a constitutional monarchy modeled on Prussia.
Over the course of just a few decades, these changes took Japan from being a semi-isolated island nation, threatened by foreign imperialism, to being an imperial power in its own right. Japan seized control of Korea, defeated Qing China in the Sino-Japanese War of 1894-95, and shocked the world by defeating the Tsar's navy and army in the Russo-Japanese War of 1904-05.
Although the Meiji Restoration caused a lot of trauma and social dislocation in Japan, it also enabled the country to join the ranks of world powers in the early 20th century. Japan would go on to ever greater power in East Asia until the tides turned against it in World War II. Today, however, Japan remains the third largest economy in the world, and a leader in innovation and technology - thanks in part to the reforms of the Meiji Restoration.