Hong Taiji is the eighth son of Nurhaci, and his biological mother is Yehenarashi Menggu. He fought with his father in his early years and was one of the four Baylors. After Nurhaci died in 1626, he was elected by Zhubeile to succeed the Khan throne, and he was changed to Yuan Tiancong the following year. At the beginning of his accession to the throne, he sat in the court with the three great bele Dai Shan, Amin, and Mang Gurtai, and his power was greatly restricted.
He gradually reduced the power of the three major Baylors. In 1632, he abolished the system of sitting side by side and realized the "independent sitting in the south". He also established the Wenguan, Liubu, Duchayuan and Lifanyuan, reused Han civil servants such as Fan Wencheng, and established the Eight Mongolian Banners and the Eight Han Army Banners. They sent troops to North Korea twice, forcing it to sever its vassal relationship with Ming Dynasty; conquered Chahar, and Monan Mongolian tribes surrendered; they also detoured to Mongolia many times and entered the hinterland of Ming Dynasty. In 1635, the family name was changed to Manchuria. In 1636, he proclaimed himself emperor in Shengjing and changed the country's name to Qing Dynasty.
Beginning in 1640, he besieged and defeated the main force of the Ming army in the Battle of Songjin, captured Hong Chengchou, the governor of Jiliao, and Ming Dynasty's defense line outside the pass collapsed. In August 1643, Hong Taiji died suddenly in Qingning Palace in Shengjing. He did not designate an heir during his lifetime, and various kings competed for the throne. Finally, his ninth son Fulin, who was only six years old, succeeded him.
Hong Taiji is the real founder of the Qing dynasty state system. He weakened the Eight Banners Baylor co-governance, established a central government office imitating the Ming Dynasty, organized the Mongolian and Han armies into the Eight Banners, united the Mongols, recruited the Han people, and transformed a tribal regime into a multi-ethnic dynasty. However, he repeatedly entered the fortress and plundered, bringing serious disasters to the people of North China; the inheritance system was unclear after his death, which almost led to civil strife.