Luchuan–Pingmian campaigns

In the middle of the fifteenth century Ming China began a series of four disastrous wars on its frontiers with Burma in Yunnan against Tai chieftainships.

The Luchuan-Pingmian Wars or Campaigns (1436–49) arose after a long period of Chinese diplomacy failed to resolve the state of endemic warfare among the Tai chieftainships that reigned along the frontier.

Events leading up to the war
From 1498 to 1504 the Ming imposed their own administrative divisions and taxation on the Tai chieftainships of the Tai-Yunnan frontier. As they did this, the frontier region gradually fell into a state of endemic warfare between the various Tai chieftainships.

In the 1530s, the intensity of the war increased, spurred on by the weakness of Ming forces after their defeat and withdrawal from Vietnam in 1427. After 1436, Tai chieftains "began to invade the border counties of central Yunnan, reaching as far as the Yung-ch’ang and Ching-tung [in Chinese territory]."

Eventually, one of the tit-for-tat seizures of territory in this state of endemic warfare triggered Chinese military intervention. In 1437 the ruler of the Tai state of Nandian requested Chinese assistance in returning land that had been taken from it by Mong Mao. The regional commander of Yunnan was requested to make an investigation into the matter and in 1438 he found that Mong Mao had "repeatedly invaded Nanlian, Ganyai, Tengchong,...Lujiang, and Jinchi" and that the Mong Mao ruler had "appointed local chieftains of the neighboring regions subordinate to him without asking for the approval of the Ming court and that some of these men joined forces with him to invade Jinchi."

The First Campaign (1438-1439)
After an initial victory, the Ming troops pursued the Tai leader deep into Tai territory. The Ming leader Fang Zheng faced problems. His troops were exhausted and his supply lines were cut off. He requested reinforcements, but few were sent. After Fang Zheng "fell into an ambush of the elephant phalanx of his enemy" he ordered his son to escape, was defeated, and died with his Ming troops.

In the wake of this defeat, Ming troops were withdrawn from the area and the Tai leader Chau-ngan-pha [Chinese: Si Ren Fa] became bolder, waging offensive warfare and attacking settlements closer to the heart of Yunnan.

The Second Campaign (1441-1442)
Although efforts by scholar officials at the Ming court were made to stop the campaigns and limit their damage and impact, a second Ming campaign to the Tai-Yunnan frontier was soon sent on its way. Eight months passed with no success in sight, when the Ming troops were ambushed by Tai troops. The Ming troops managed to fight the Tai troops off and lead an attack on the stronghold of the Tai leader Si Ren-fa. The Tai side was defeated with 50,000 deaths. A small group of around 1000 under the leadership of Si Ren-fa managed to flee.

Third Campaign (1443-1444)
The third campaign managed to remove Si Ren-fa from power with the help of the Burmese kingdom of Ava. Si Ren-fa's son Chau-si-pha [Chinese: Si Jifa] escaped capture, however, and established a power base at Mong Yang (Mengyang) on the west bank of the Irrawaddy river.

Fourth Campaign (1449)
A fourth campaign was sent in 1449 to capture Si Jifa, but failed to achieve this main objective. The Chinese allowed remnants of the defeated Tai ruling elite to remain in Mong Yang if they agreed never to cross the Irrawaddy river to the east.

Chinese sources disagree about how Si Jifa finally met his end, one Shan chronicle even claiming he reigned for another fifty years. The version of events found in the official Chinese history includes one possible motive for the Tai invasion of Ava in 1524-27, revenge:

"Si Jifa [Chau-si-pha] escaped to Mengyang [Mong Yang] in early 1449 but was caught by the chieftain of Ava-Burma. In April 1454 the chieftain of Ava-Burma asked the Chinese to revert the land to him and the Ming ceded Yinjia to Burma, so Si Jifa and his family, a total of six people, were delivered to the Ming troops at a village on Upper Irrawaddy. Si Jifa [Chau-sipha] was immediately escorted to the capital where he was executed. However, Ava-Burma let Si Bufa, the younger brother of Si Jifa, go free. He and his son, Si Hongfa (Thohanbwa) continued to rule Mengyang without the official approval of the Ming court. They sent tribute missions to China, but the court kept a close eye on the matter. Early in the Jiajing reign one of the descendants of Si Renfa [Chau-ngan-pha, Thonganbwa], then ruling Mengyang, managed to take revenge. In 1527 (Jiajing 6) he led an army that marched south to invade Ava-Burma, killing the chieftain Mang-ji-si (Shwenankyawshin) [Narapati (1502-1527)] and his wife."

Consequences of the Wars
As the historian Wang Gungwu observes:

"This war had disastrous consequences for the Ming state, it disrupted the economies of all the southwestern provinces involved in sending men and supplies in fighting a war of attrition against a small tribal state and it cost the Ming state the respect of its tribal allies on the border, who saw how inept and wasteful the Ming armies were. Moreover, the war drew commanders, officers, men, and other resources from the north which might have been vital to the defence of the northern borders. It is significant that the end of the Lu-ch’uan campaigns early in 1449 was followed immediately by extensive tribal uprisings and other revolts in five provinces south of the Yangtze river, and, on the northern frontiers, by the spectacular defeats later in the year which virtually destroyed the imperial armies in the north and led to the capture of the emperor himself by the Mongols. The year 1449 was a turning point in the history of the dynasty."

Another important consequence of the wars is that the Ming favored diplomacy from this time hence and shunned any military action along the frontier.