The Qing dynasty (Chinese: 清朝; pinyin: Qīng Cháo; Wade–Giles: Ch'ing Ch'ao), officially the Great Qing (大清; Dà Qīng), also called the Empire of the Great Qing or the Manchu dynasty, was the last imperial dynasty of China, ruling from 1644 to 1912 with a brief, abortive restoration in 1917. It was preceded by the Ming dynasty and succeeded by the Republic of China. The Qing multi-cultural empire lasted almost three centuries and formed the territorial base for the modern Chinese state. The dynasty was founded by the Jurchen Aisin Gioro clan in Manchuria. In the late sixteenth century, Nurhaci, originally a Ming vassal, began organizing "Banners", military-social units that included Jurchen, Han Chinese, and Mongol elements. Nurhaci formed the Jurchen clans into a unified entity, which became known as Manchus. By 1636, his son Hong Taiji began driving Ming forces out of Liaodong and declared a new dynasty, the Qing. In 1644, peasant rebels led by Li Zicheng conquered the Ming capital Beijing. Rather than serve them, Ming general Wu Sangui made an alliance with the Manchus and opened the Shanhai Pass to the Banner Armies led by Prince Dorgon, who defeated the rebels and seized Beijing. The conquest of China proper was not completed until 1683 under the Kangxi Emperor (r. 1661–1722). The Ten Great Campaigns of the Qianlong Emperor from the 1750s to the 1790s extended Qing control into Central Asia. While the early rulers maintained their Manchu ways, and while their official title was Emperor they were known as khans to the Mongols and patronized Tibetan Buddhism, they governed using Confucian styles and institutions of bureaucratic government. They retained the imperial examinations to recruit Han Chinese to work under or in parallel with Manchus. They also adapted the ideals of the tributary system in dealing with neighboring territories. The reign of the Qianlong Emperor (1735–1796) saw the dynasty's apogee and initial decline in prosperity and imperial control. The population rose to some 400 million, but taxes and government revenues were fixed at a low rate, virtually guaranteeing eventual fiscal crisis. Corruption set in, rebels tested government legitimacy, and ruling elites did not change their mindsets in the face of changes in the world system. Following the Opium War, European powers imposed unequal treaties, free trade, extraterritoriality and treaty ports under foreign control. The Taiping Rebellion (1850–64) and the Dungan Revolt (1862–77) in Central Asia led to the deaths of some 20 million people, most of them due to famines caused by war. In spite of these disasters, in the Tongzhi Restoration of the 1860s, Han Chinese elites rallied to the defense of the Confucian order and the Qing rulers. The initial gains in the Self-Strengthening Movement were destroyed in the First Sino-Japanese War of 1895, in which the Qing lost its influence over Korea and the possession of Taiwan. New Armies were organized, but the ambitious Hundred Days' Reform of 1898 was turned back by Empress Dowager Cixi, a ruthless but capable leader. When the Scramble for Concessions by foreign powers triggered the violently anti-foreign Yihetuan ("Boxers"), the foreign powers invaded China, the Empress Dowager declared war on them, leading to defeat and the flight of the Imperial Court to Xi'an. After agreeing to sign the Boxer Protocol the government then initiated unprecedented fiscal and administrative reforms, including elections, a new legal code, and abolition of the examination system. Sun Yat-sen and other revolutionaries competed with reformers such as Liang Qichao and monarchists such as Kang Youwei to transform the Qing empire into a modern nation. After the death of Empress Dowager Cixi and the Guangxu Emperor in 1908, the hardline Manchu court alienated reformers and local elites alike. Local uprisings starting on October 11, 1911 led to the Xinhai Revolution. Puyi, the last emperor, abdicated on February 12, 1912.