The military history of Myanmar (Burma) spans over a millennium, and is one of the main factors that have shaped the history of the country, and to a certain degree, the history of Southeast Asia. At various times in history, successive Burmese kingdoms were also involved in warfare against their neighbouring states in the surrounding regions of modern Burmese borders—from Bengal, Manipur and Assam in the west, to Yunnan (the southern China) in the northeast, to Laos and Siam in the east and southeast.
The Royal Burmese Army was a major Southeast Asian armed force between the 11th and 13th centuries and between 16th and 19th centuries. The Mongol invasions (1277–1301) were an existential threat to the country. Burma was the premier military force in the 16th century. The First Toungoo Empire was the largest empire in Southeast Asian history.Lieberman 2003: 152 The centuries-long warfare between Burma and Siam (1547–1855) shaped the history of both countries and Mainland Southeast Asia. The Manchu invasions (1765–1769) were the primary threat to Burma in the 18th century. The Konbaung kings encountered the British in what's now Northeast India in the early 19th century.Lieberman 2003: 32Myint-U 2006: 107–127 Three Anglo-Burmese wars (1824–1885) were fought and Burma lost. The Burmese monarchy of the Konbaung dynasty was abolished in 1885. The British fully annexed Burma as part of British India in 1886.
The country was a major battle front in the Southeast Asian theatre of World War II. Burma gained independence from the British in 1948. The Myanmar conflict has been ongoing between various political and ethnic factions since 2 April 1948. A myriad of insurgencies received implicit and explicit support from several external countries.
Early history The military history in the early era is sketchy. The Tibeto-Burman-speaking Pyu, the earliest inhabitants of the Irrawaddy valley in recorded history, founded several city states that thrived between the 1st century BCE and the early 9th century CE. In the 8th century CE, Chinese records identify 18 Pyu states throughout the Irrawaddy valley and describe the Pyu as a humane and peaceful people to whom the war was virtually unknown and who wore silk cotton instead of actually silk so that they would not have to kill silkworms.Hall 1960: 8–10 To be sure, this peaceful description by the Chinese was a snapshot of the Pyu realm, and may not represent the life in the city-states in general.
The earliest extant record of warfare in the Pyu realm in the early 9th century when the Pyu states came under constant attacks by the armies of the Kingdom of Nanzhao (from present-day Yunnan). Nanzhao had just become a major military power in the region by defeating the Tibetan Empire in 801. The Nanzhao warriors then pressed down southward into the present-day Shan Hills and into the Irrawaddy valley. Ancient city-states one by one surrendered or were overrun by the "powerful mounted archers from the north". In 832, Nanzhao destroyed the city-state of Halin, close to old Tagaung, returning again in 835 to carry off many captives. The Nanzhao cavalry is said to have swept down all the way to the Bay of Bengal despite stiff resistance.Myint-U 2006: 54–55
Pagan period Following the Nanzhao raids, another Tibeto-Burman-speaking people called the Mranma (Burmans or Bamar), who had come down with the Nanzhao raids, began to settle the central Irrawaddy valley, near the confluence of the Irrawaddy and Chindwin rivers, en masse. The Burmans founded a small fortified city of Pagan (Bagan) c. 849, probably to help the Nanzhao pacify the surrounding country side.Myint-U 2006: 56–57 The early Pagan army consisted mainly of conscripts raised just prior to or during the times of war. The main weaponry of the infantry largely consisted of swords, spears and bow and arrows. The infantry units were supported by cavalry and elephantry corps. The Pagan army would later be known to the world for their war elephants as reported by Marco Polo.
Pagan Empire
By King Anawrahta's accession in 1044, the small principality had gradually grown to include its immediate surrounding area—to about 200 miles north to south and 80 miles from east to west.Harvey 1925: 24–25 Over the next 30 years, Anawrahta went on to unify for the first time the regions that would later constitute the modern-day Burma. Anawrahta began his campaigns in the nearer Shan Hills, and extended conquests to Lower Burma down to the Tenasserim coast to Phuket and North Arakan. Anawrahta's conquest of Tenasserim checked the Khmer Empire's encroachment in the Tenasserim coast, and secured control of the peninsula ports, which were transit points between the Indian Ocean and China.Lieberman 2003: 94
After a flurry of military campaigns by Anawrahta, Pagan entered a gilded age that would last for the next two centuries. Aside from a few occasional rebellions, the kingdom was largely peaceful during the period. The most serious was the 1082–1084 rebellion by Pegu (Bago), which nearly toppled the Pagan regime. In the 1110s, Pagan sent two separate expeditions to Arakan to place its claimant Letya Min Nan on the Arakanese throne. The first expedition failed but the second in 1118 succeeded.Arakanese chronicles give 1103, not 1118. Sinhalese Mahavamsa Chronicles mention a dispute over trade in elephants between Burma and Sri Lanka that prompted the Ceylonese forces to raid Lower Burma in 1180.Harvey 1925: 328
The authority of Pagan continued to grow, peaking in the reign of King Narapatisithu (r. 1174–1211). The king formally founded the Royal Palace Guards in 1174, the first extant record of a standing army. Pagan's influence reached further south into the northern Malay Peninsula, at least to the Salween river in the east, below the current China border in the farther north, and to the west, northern Arakan and the Chin Hills.Lieberman 2003: 91 Up to the first half of the 13th century, much of mainland Southeast Asia was under some degree of control of either the Pagan Empire or the Khmer Empire.
Late 13th century rebellions The Pagan military power was closely intertwined with the kingdom's economic prowess. The kingdom went into decline in the 13th century as the continuous growth of tax-free religious wealth—by the 1280s, two-thirds of Upper Burma's cultivable land had been alienated to the religion—affected the crown's ability to retain the loyalty of courtiers and military servicemen. This ushered in a vicious circle of internal disorders and external challenges by Mons, Mongols and Shans.Lieberman 2003: 119–123
The first signs of disorder appeared soon after Narathihapate's accession in 1256. The inexperienced king faced revolts in Arakanese state of Macchagiri (present-day Kyaukpyu District)(Harvey 1925: 326–327): the location of Macchagiri was likely west of Thayet on the western side of the Arakan Yoma; Harvey's map of Pagan Empire on p. 21 shows present-day Kyaukpru District (specifically, Ann) as Macchagiri. in the west, and Martaban (Mottama) in the south. The Martaban rebellion was easily put down but Macchagiri required a second expedition before it too was put down.Harvey 1925: 62 The calm did not last long. Martaban again revolted in 1285.
Mongol invasions
This time, Pagan could not do anything to retake Martaban because it was facing an existential threat from the north. The Mongols demanded tribute, in 1271 and again in 1273. When Narathihapate refused both times, the Mongols systematically invaded the country. The first invasion in 1277 defeated the Burmese at the battle of Ngasaunggyan, and secured their hold of Kanngai (modern-day Yingjiang, Yunnan, 112 km north of Bhamo). In 1283–1285, their forces moved south and occupied down to Tagaung and Hanlin. The king fled to Lower Burma in 1285 before agreeing to submit to the Mongols in June 1286.Myint-U 2006: 60–62Than Tun 1964: 136–137 Soon after the agreement was finalised, the king was assassinated in July 1287. The Mongols once again invaded south toward Pagan.
Recent research indicates that Mongol armies may not have reached Pagan itself, and that even if they did, the damage they inflicted was probably minimal.Lieberman 2003: 119 But the damage was already done. All the vassal states of Pagan revolted right after the king's death, and went their own way. In the south, Wareru, the man who had seized the governorship of Martaban in 1285, consolidated Mon-speaking regions of Lower Burma, and declared Ramannadesa (Land of the Mon) independent in 1287. In the west too, Arakan stopped paying tribute.Harvey 1925: 68 The 250-year-old Pagan Empire had ceased to exist.
Warring states period The political vacuum created by the sudden collapse of Pagan triggered constant warfare that would engulf the Irrawaddy valley and its periphery for the next 350 years. In retrospect, the two centuries of peace and order maintained by the Pagan Empire turned out to be rather remarkable. The main cause for warfare was that no strong polity emerged to reunite the kingdom. After their 1287 invasion, the Mongols moved farther south to Tagaung but refused to fill in the power vacuum they had created. Indeed, Emperor Kublai Khan never sanctioned an actual occupation of Pagan. His real aim appeared to have been "to keep the entire region of Southeast Asia broken and fragmented."Htin Aung 1967: 83
Last Mongol invasion
At Pagan, the new king Kyawswa controlled just a small area outside the capital. Instead, the real power rested with three former Pagan commanders of nearby Myinsaing. It was the brothers, not the nominal sovereign Kyawswa, that sent a force to retake Lower Burma in 1294 after Wareru had decided to become a vassal of the Sukhothai Kingdom. Wareru drove back the Myinsaing forces.Htin Aung 1967: 79
Concerned by the increasing power of the three brothers, Kyawswa submitted to the Mongols in January 1297, and was recognised by the Mongol emperor Temür Khan as viceroy of Pagan on 20 March 1297. In December 1297, the three brothers overthrew Kyawswa, and founded the Myinsaing Kingdom. In January 1300, the Myinsaing forces led by Athinhkaya seized the southernmost Mongol garrisons named Nga Singu and Male, just north of modern Mandalay. On 22 June 1300, the Mongol Emperor declared that Kumara Kassapa, one of Kyawswa's sons, was the rightful king of Burma, and sent in a 12,000-strong army from Yunnan. The Mongol army reached Male on 15 January 1301, and Myinsaing on 25 January. But they could not break through. The besiegers took the bribes given by the three brothers, and began their retreat on 6 April. But the commanders were executed by the Yunnan government when they got back.Than Tun 1959: 121–122 The Mongols sent no more invasions, and withdrew entirely from Upper Burma on 4 April 1303.Htin Aung 1967: 73–75Than Tun 1964: 137
First Shan raids The Mongols left but the Shan people, who had come down with the Mongols did not—just as the Burmans who came down with the Nanzhao invasions stayed behind four centuries earlier. The Shans built an array of small states in the entire northwestern to eastern arc of central Burma, thoroughly surrounding the valley. They continued to raid the Irrawaddy valley throughout the 14th century, taking advantage of the split of Myinsaing into Pinya and Sagaing kingdoms in 1315. Starting in 1356, then the most powerful Shan state of Mogaung (in present-day Kachin State) began a series of sustained assaults on central Burma. In 1364, its forces sacked both Sagaing and Pinya in succession, and left off with the loot.