The Qing Myanmar campaign (1765-1770) was the most disastrous frontier war that the Qing dynasty had ever waged. In the beginning, the Qianlong emperor (r. 1735-1795) of the Qing dynasty had envisaged winning this war in one easy stroke, as he deemed Myanmar no more than a remote barbarian tribe without any power. But he was wrong. After the Green Standard troops in Yunnan failed to bring the Myanmar to their knees, Qianlong sent his elite Manchu troops in. A regional conflict was thus escalated into a major frontier war that involved military maneuvers nationwide. At the front, the Manchu Bannermen had to deal with the unfamiliar tropical jungles and swamps, and above all, the lethal endemic diseases. Not only did one after another commander-in-chief of the Qing dynasty fail to conquer Myanmar, but the Qing troops also suffered extremely heavy casualties. After a gruelling four-year campaign, a truce was reached by the field commanders of the two sides at the end of 1769 with the Qing invading expedition failing to conquer Myanmar and withdrawing in disarray. To rehabilitate itself, the Qing dynasty kept a heavy military lineup in the border areas of Yunnan for about one decade in an attempt to wage another war while imposing a ban on inter-border trade for two decades.