Hong Taiji in the context of "Jurchen unification"

Manchuria is a region in East Asia. Depending on the definition of its extent, Manchuria can refer either to a region falling entirely within present-day China, or to a larger region today divided between Northeast China and the Russian Far East. To differentiate between the two parts following the latter definition, the Russian part is also known as Outer Manchuria (or Russian Manchuria), while the Chinese part is known as Northeast China.

Manchuria is the homeland of the Manchu people. "Manchu" is a name introduced by Hong Taiji of the Qing dynasty in 1636 for the Jurchen people, a Tungusic people.

The Qing dynasty (/tʃɪŋ/ CHING), officially the Great Qing, was a Manchu-led imperial dynasty of China and an early modern empire in East Asia. The last imperial dynasty in Chinese history, the Qing dynasty was preceded by the Ming dynasty and succeeded by the Republic of China. At its height of power, the empire stretched from the Sea of Japan in the east to the Pamir Mountains in the west, and from the Mongolian Plateau in the north to the South China Sea in the south. Originally emerging from the Later Jin dynasty founded in 1616 and proclaimed in Shenyang in 1636, the dynasty seized control of the Ming capital Beijing and North China in 1644, traditionally considered the start of the dynasty's rule. The dynasty lasted until the Xinhai Revolution of October 1911 led to the abdication of the last emperor in February 1912. The multi-ethnic Qing dynasty assembled the territorial base for modern China. The Qing controlled the most territory of any dynasty in Chinese history, and in 1790 represented the fourth-largest empire in world history to that point. With over 426 million citizens in 1907, it was the most populous country at the time.

Nurhaci, leader of the Jianzhou Jurchens and House of Aisin-Gioro who was also a vassal of the Ming dynasty, unified Jurchen clans (known later as Manchus) and founded the Later Jin dynasty in 1616, renouncing the Ming overlordship. As the founding Khan of the Manchu state he established the Eight Banners military system, and his son Hong Taiji was declared Emperor of the Great Qing in 1636. As Ming control disintegrated, peasant rebels captured Beijing as the short-lived Shun dynasty, but the Ming general Wu Sangui opened the Shanhai Pass to the Qing army, which defeated the rebels, seized the capital, and took over the government in 1644 under the Shunzhi Emperor and his prince regent. While the Qing became a Chinese empire, resistance from Ming rump regimes and the Revolt of the Three Feudatories delayed the complete conquest until 1683, which marked the beginning of the High Qing era. As an emperor of Manchu ethnic origin, the Kangxi Emperor (1661–1722) consolidated control, relished the role of a Confucian ruler, patronised Buddhism, encouraged scholarship, population and economic growth.

Jurchen (Manchu: ᠵᡠᡧᡝᠨ, romanized: Jušen, [dʒuʃən]; Chinese: 女真, romanized: Nǚzhēn, [nỳ.ʈʂə́n]) were a number of East Asian Tungusic-speaking people. They lived in northeastern China, also known as Manchuria, before the 18th century. The Jurchens were renamed Manchus in 1635 by Hong Taiji. The Jurchens were culturally diverse, with different groups living as hunter-gatherers, pastoralist semi-nomads, or sedentary agriculturists. Generally lacking a central authority, and having little communication with each other, many Jurchen groups fell under the influence of neighbouring dynasties, their chiefs paying tribute and holding nominal posts as effectively hereditary commanders of border guards.

Han officials of the Ming dynasty (1368–1644) classified them into three groups, reflecting relative proximity to the Ming:

The Shunzhi Emperor (15 March 1638 – 5 February 1661), also known by his temple name Emperor Shizu of Qing, personal name Fulin, was the second emperor of the Qing dynasty, and the first Qing emperor to rule over China proper. Upon the death of his father Hong Taiji, a committee of Manchu princes chose the 5-year-old Fulin as successor. The princes also appointed two co-regents: Dorgon, the 14th son of Nurhaci, and Jirgalang, one of Nurhaci's nephews, both of whom were members of the Aisin-Gioro clan. In November 1644, the Shunzhi Emperor was enthroned as emperor of China in Beijing.

From 1643 to 1650, political power lay mostly in the hands of the prince regent Dorgon. Under his leadership, the Qing conquered most of the territory of the fallen Ming dynasty, chased Ming loyalist regimes deep into the southwestern provinces, and established the basis of Qing rule over China proper despite highly unpopular policies such as the "hair cutting command" of 1645, which forced all Qing male subjects to shave their forehead and braid their remaining hair into a queue resembling that of the Manchus. After Dorgon's death on the last day of 1650, the young Shunzhi Emperor started to rule personally. He tried, with mixed success, to fight corruption and to reduce the political influence of the Manchu nobility. In the 1650s, he faced a resurgence of Ming loyalist resistance, but by 1661 his armies had defeated the Qing's last enemies, Koxinga and the Prince of Gui, both of whom would succumb the following year.

The Later Jin, officially known as Jin or the Great Jin, was a Jurchen-led royal dynasty of China and a khanate ruled by the House of Aisin-Gioro in Manchuria, as the precursor to the Qing dynasty. Established in 1616 by the Jianzhou Jurchen chieftain Nurhaci upon his reunification of the Jurchen tribes, its name was derived from the earlier Jin dynasty founded by the Wanyan clan which had ruled northern China in the 12th and 13th centuries.

In 1635, the lingering Northern Yuan dynasty under Ejei Khan formally submitted to the Later Jin. The following year, Hong Taiji officially renamed the realm to "Great Qing", thus marking the start of the Qing dynasty. During the Ming–Qing transition, the Qing conquered Li Zicheng's Shun dynasty and various Southern Ming claimants and loyalists, going on to rule an empire comprising all of China, stretching as far as Tibet, Manchuria, Mongolia, Xinjiang, and Taiwan until the 1911 Revolution established the Republic of China.

The Eight Banners (in Manchu: ᠵᠠᡴᡡᠨ
ᡤᡡᠰᠠ jakūn gūsa, Chinese: 八旗; pinyin: bāqí; Wade–Giles: pa-ch'i, Mongolian: ᠨᠠᠶᠢᠮᠠᠨ
ᠬᠣᠰᠢᠭᠤ) were administrative and military divisions under the Later Jin and Qing dynasties of China into which all Manchu households were placed. In war, the Eight Banners functioned as armies, but the banner system was also the basic organizational framework of all of Manchu society. Created in the early 17th century by Nurhaci, the banner armies played an instrumental role in his unification of the fragmented Jurchen people (who would later be renamed the "Manchu" under Nurhaci's son Hong Taiji) and in the Qing dynasty's conquest of the Ming dynasty.

As Mongol and Han forces were incorporated into the growing Qing military establishment, the Mongol Eight Banners and Han Eight Banners were created alongside the original Manchu banners. The banner armies were considered the elite forces of the Qing military, while the remainder of imperial troops were incorporated into the vast Green Standard Army. Membership in the banners became hereditary, and bannermen were granted land and income. After the defeat of the Ming dynasty, Qing emperors continued to rely on the Eight Banners in their subsequent military campaigns. After the Ten Great Campaigns of the mid-18th century the quality of the banner armies declined. Their failure to suppress the Taiping Rebellion of the mid-19th century ruined their reputation. By the late 19th century the task of defending the empire had largely fallen upon regional armies such as the Xiang Army. Over time, the Eight Banners became synonymous with Manchu identity even as their military strength vanished.