by a coalition of rebel forces led by Li Zicheng, a former minor Ming official, who established a short-lived Shun dynasty. The last Ming ruler, the Chongzhen Emperor, committed suicide when the city fell to the rebels, marking the official end of the dynasty. Li Zicheng then led rebel forces numbering some 200,000 to confront Wu Sangui, at Shanhai Pass, a key pass of the Great Wall, which defended the capital. Wu Sangui, caught between a Chinese rebel army twice his size and a foreign enemy he had fought for years, cast his lot with the familiar Manchus. Wu Sangui may have been influenced by Li Zicheng's mistreatment of wealthy and cultured officials, including Li's own family; it was said that Li took Wu's concubine Chen Yuanyuan for himself. Wu and Dorgon allied in the name of avenging the death of the Chongzhen Emperor. Together, the two former enemies met and defeated Li Zicheng's rebel forces in battle on May 27, 1644. The newly allied armies captured Beijing on 6 June. The Shunzhi Emperor was invested as the "Son of Heaven" on 30 October. The Manchus, who had positioned themselves as political heirs to the Ming emperor by defeating Li Zicheng, completed the symbolic transition by holding a formal funeral for the Chongzhen Emperor. However, conquering the rest of China Proper took another seventeen years of battling Ming loyalists, pretenders and rebels. The last Ming pretender, Prince Gui, sought refuge with the King of Burma, Pindale Min, but was turned over to a Qing expeditionary army commanded by Wu Sangui, who had him brought back to Yunnan province and executed in early 1662. The Qing had taken shrewd advantage of Ming civilian government discrimination against the military and encouraged the Ming military to defect by spreading the message that the Manchus valued their skills. Banners made up of Han Chinese who defected before 1644 were classed among the Eight Banners, giving them social and legal privileges. Han defectors swelled the ranks of the Eight Banners so greatly that ethnic Manchus became a minority—only 16% in 1648, with Han Bannermen dominating at 75% and Mongol Bannermen making up the rest. Gunpowder weapons like muskets and artillery were wielded by the Chinese Banners. Normally, Han Chinese defector troops were deployed as the vanguard, while Manchu Bannermen acted as reserve forces or in the rear and were used predominantly for quick strikes with