Tianqi Emperor
When the Tianqi Emperor died in October 1627, he had no surviving heir (his last son died a year prior during the mysterious Wanggongchang Explosion). As the emperor's brother, Zhu Youjian, then about 16 years old, ascended the throne as the Chongzhen Emperor. His succession was helped by Empress Zhang (widow of the Tianqi Emperor), despite the manoeuvres of the chief eunuch, Wei Zhongxian, who wanted to continue to dominate the imperial court. From the beginning of his rule, the Chongzhen Emperor did his best to stem the decline of the Ming dynasty. His efforts at reform focused on the top ranks of the civil and military establishment. However, years of internal corruption and an empty treasury made it almost impossible to find capable ministers to fill important government posts. The emperor also tended to be suspicious of his subordinates, executing dozens of field commanders, including general Yuan Chonghuan, who had directed the defence of the northern frontier against the Manchu (later known as the Qing dynasty). The Chongzhen Emperor's reign was marked by his fear of factionalism among his officials, which had been a serious issue during the reign of the Tianqi Emperor. Soon after his brother's death, the Chongzhen Emperor immediately eliminated Wei Zhongxian and Madam Ke, as well as other officials thought to be involved in the "Wei-Ke conspiracy".