First Mongol invasion of Burma

After the conquest of China, Kublai Khan, the founder of the Yuan Dynasty and the Great Khan of the Mongol Empire, invaded the Pagan Kingdom of Burma in 1277 and 1283. However, the Yuan armies later again invaded Burma several times in order to assert supremacy over the territory.

Initial conflicts of 1277
After the conquest of Yunnan in 1253, there was an open route to Indochina. Kublai, the founder of the Yuan Dynasty and the fifth Great Khan of the Mongol Empire, dispatched Sayid Ajall as the administrator of Yunnan province in 1273. Then Kublai sent three envoys to demand Burma's submission.

During that period, Burma was in a state of turmoil. The royal treasury had been deteriorating for years because the continued growth of tax-free religious landholdings. Rebellions broke out in Arakan and in Tenasserim but quelled by the chief minister Yazathingyan who died in the return journey. The Burmese king Narathihapate was incompetent in both domestic and foreign affairs. With the old minister's death removed the only person that could have controlled the ruthless, inexperienced king. He received Mongol envoys well at first but executed them when they arrived the second time. Narathihapate then invaded the Thai state of Kaungai because its chief had recently defected to Yuan.

In 1277 the Burmese, with 80-200 war elephants, had advanced over the border along the high valleys in Baoshan. 700 man Mongol garrison under Khudu was sent to blockade their way with Achang and Gold-tooth tribesmen (said to number 12,000 men). The Mongol horses refused to advance when they saw elephants. Khudu ordered his men to dismount, approach on foot and shower the elephants with arrows. Wounded by those arrows, the elephants plunged into the forest, destroying everything in their path, including the Burmese infantry. The Burmese fled, though Khudu was wounded during the armed clash with the Burmese at Nandian. The Yuan troops returned to Yunnan, carrying their wounded commander.

An army of 3,840 Mongols, Yi, Mosuo under Sayid's son Nasr al-Din invaded Burma in November, 1277 and he defeated another Burmese army. Nasr counted households and set up postal stations in the area. But he withdrew to avoid heat and malaria.

Mongol offensives of 1283
In 1283, the Yuan force of 10,000 under the Mongol prince Sangudar from Sichuan, with the Miao auxiliaries, advanced to induce the king to submit. The Mongol army advanced in two columns, the first column by the river Taping by Manwaing (200 boats) and the second column by land.

The Mongols defeated the Burmese army at the fortified stockade at Ngatshaungyan (alternative names: Kiang thu, Kaun taung), south of Bhamo. A second defeat of the Burmese army took place on the eastern bank of the Irrawaddy River opposite of Male, Myanmar, south of Bhamo. The Burmese army suffered a loss of more than 10,000 men.

The fighting went on and off in the following years, punctuated by attempts at negotiation including a mission in 1284 by the minister Dithapamoukka to the court of Kublai Khan. The king fled Pagan in panic to Lower Burma. Among his subjects, he is forever remembered as Tayokpyay Min, or the King who Ran Away from the Chinese.

Fall of Pagan 1287
Narathihapate had been just assassinated by his son Thihathu when Kublai decided to send his troops again in late 1286. The prince Esen-temur led his 7,000 men down the Irrawaddy. When he reached Pagan, the king had already fled to the hills nearby. The Yuan troops stripped Pagan's monasteries of their gold and silver and rape, murder, arsons the city. Esen-temur divided Burma into the Yuan's political divisions and installed the puppet ruler of the Mongols. However, the Mongol rule was short lived and the Pagan Kingdom fell into anarchy.

Aftermath
In 1297 Thihathu's brother Tribuhuvanaditya, the king of Pagan, submitted to the Yuan court. In response to this friendly action, Temür Khan (r.1294-1307), the successor of Kublai Khan, stopped his plan to attack Burma. In 1299 a Burmese official called Asange killed the king Tribuhuvanaditya as well as over a hundred messengers from the Yuan Dynasty by the order of the former king's younger brother Athinkiya. Thus, Temür Khan decided to send army to punish him. Nevertheless, the Yuan army from Yunnan Xing Zhongshusheng met significant resistance. Burmese nobles reasserted control over some territories in Burma with Mongols and drove out Shan-Thais. But at the another fortified, three-walled town of Myinsaing, Shan forces checked the Mongols, of whom about 500 were killed in battle in 1300. In the next year, Asange decided to bribe the Yuan generals, which was successful and the Yuan army retreated to China soon. Later, the Mongol commander was executed by Yunnan's governor for his actions. Asange sent his younger brother to the Yuan court to ask for pardon, and Temür agreed to stop the Burmese campaign.

Legacy
During the official visit by the President Tsakhiagiin Elbegdorj to Myanmar in November 2013, Aung San Suu Kyi, the chairperson of National League for Democracy, said this is the first ever Mongol mission since the Mongols came 730 years earlier.