The Ava–Hanthawaddy War (1385–1391) (Burmese: အင်းဝ–ဟံသာဝတီ စစ် (၁၃၈၅–၁၃၉၁)) was a military conflict between Ava and Hanthawaddy Pegu, both kingdoms located in present-day Myanmar, that lasted from 1385 to 1391. It was the first of the four decades-long wars between the two kingdoms. Hanthawaddy's victory over a far larger Ava in this war preserved the nascent kingdom's independence.
The war's immediate origins trace to Hanthawaddy's deep political turmoil following King Razadarit's contentious rise to power in 1384. The 16-year-old king, who had seized the throne after having raised a rebellion against his ailing father King Binnya U, faced several rebellions by his father's vassals. The crisis escalated in 1385 when Viceroy Laukpya of the Province of Myaungmya persuaded King Swa Saw Ke of Ava to put him on the Hanthawaddy throne. Swa underestimated Razadarit, and sent down two small armies led by his two young sons, Crown Prince Tarabya and Prince Min Swe. When his bickering sons came back empty-handed after a badly coordinated campaign five months later, Swa himself invaded with much larger land and riverine forces. Ava forces penetrated as far south as Dagon and Dala but they could not overcome formidable Hanthawaddy fortifications, and had to withdraw by mid 1387.
The two failed campaigns ushered a new entrant into the fray. Ava's longtime enemy Maw (Mong Mao) began raiding its northernmost districts, forcing Swa to suspend his southern operations until a truce with Maw was reached in 1389/90. Razadarit took full advantage and captured two provinces he did not yet control—Martaban and Myaungmya—as well as two border towns inside Ava territory by early 1390. In response, Swa launched another major invasion that year but his forces could not even get past the border. Faced with another embarrassing defeat, Swa grudgingly accepted Razadarit's peace offer, in which Ava agreed to recognize Pegu in exchange for Pegu returning the border towns. Tensions remained high until Swa withdrew his last regiments from the Tharrawaddy front later in 1391.
In the following decade, Hanthawaddy-Pegu under Razadarit's leadership became more unified, and grew to be a major regional power. On the other hand, Ava remained preoccupied with the Maw threat throughout the 1390s. When Ava entered into a succession crisis in 1400, Razadarit felt powerful enough that he invaded his larger and more populous northern neighbor, starting the Ava–Hanthawaddy War (1401–1403).
Background
The origins of the war trace back to the two kingdoms' lukewarm relationship since the early 1370s as well as Ava's long-running problems with its northern neighbor, Shan-speaking Maw (Mong Mao).
Emergence of Ava and Hanthawaddy Pegu
Both kingdoms emerged in the 1360s. The central-dry zone-based Ava was founded in 1365 as a remnant of the Pinya and Sagaing kingdoms, after Maw raids left the two kingdoms in tatters. When Ava's founder Thado Minbya died in 1367, his successor Swa Saw Ke inherited a largely embryonic polity that controlled few peripheral regions. On the southern coast, the polity based out of Pegu (Bago) came into being as a remnant of the Martaban Kingdom in 1369/70 when King Binnya U was forced to retreat to the hitherto provincial capital by his cousins Byattaba and Laukpya, who had waged a rebellion since 1364.
Early relations
It was during these turbulent times that the first peace treaty between the two rump kingdoms was signed in 1370/71. The initial proposal came from U, who wanted to keep his northern border quiet. Swa, who wanted U's assurance that Pegu would not help the former southern vassals of Pinya, accepted.
The treaty allowed both kings to focus on their domestic struggles. Though U regained Donwun from Byattaba in 1371, the king was soon forced to make peace when his cousins sought an intervention by the kingdom of Lan Na (in present-day northern Thailand). The king agreed to recognize them as the autonomous viceroys of Martaban and Myaungmya provinces, respectively; in return, the brothers agreed to nominally recognize U as their sovereign.
Swa was far more successful in expanding his authority. He promptly went to war with Maw, and by 1373 had seized Kale (Kalay) and Myedu from Maw. Later in 1373 (or early 1374), he placed his nominee on the vacant throne of Arakan. He then plotted to replace Governor Pyanchi I of Toungoo, who he felt was too close to Pegu.
Deterioration of relations
The relations between the kingdoms suddenly cooled in 1375 when Pyanchi I revolted. According to the main royal chronicles, Pegu sent a sizable military force to Toungoo (Taungoo) to aid the rebellion. Ava had to send three separate expeditions to regain Toungoo in 1375–1376. However, the Razadarit Ayedawbon, the chronicle that covers the early Hanthawaddy period from the Hanthawaddy perspective, makes no mention of Pegu's support of Toungoo in any way during this period; instead, it portrays U as an ailing king whose effective authority amounted to a single province, not one capable of interfering in others' affairs. In any case, it was only in 1383 when Pegu was amidst a serious rebellion that Ava was able to install its preferred governor at the border state. The Ava regime watched on as Pegu's political instabilities worsened after Binnya U's death in 1384. Their subsequent decision to interfere in the southern kingdom's affairs would lead to war.
Prelude to the war
Instabilities in Pegu
Pegu's succession crisis began in May 1383 when Prince Binnya Nwe raised a rebellion against his ailing father (and his aunt and adoptive mother Princess Maha Dewi). The young prince went on to seize the throne, after U's death in January 1384. However, the 16-year-old new king, now known by his regnal title Razadarit, could not get any of the key vassals outside his home province to acknowledge him. Governor Smin Sam Lek of Donwun, a Binnya U loyalist, deemed Razadarit a mere usurper while viceroys Byattaba of Martaban and Laukpya of Myaungmya, who had indirectly supported the prince's rebellion, refused to submit now that the rebellion had succeeded.
Laukpya's request
"... I, Laukpya, Lord of Myaungmya, bowed at thy feet, O king of the Golden Palace at Ava, and pray that thou march against Razadarit before he is firm upon his throne. I will bring men by water. When we have conquered him, do thou keep the heart-wood and leave me the bark."
Laukpya in particular wanted to take over Pegu. Since he could not take on the most populous province on his own, he considered seeking Ava's help, just as the brothers sought Lan Na's help in the 1370s. However, Byattaba, whose territory bordered the Tai states to the east, demurred. Laukpya ultimately decided to act on his own, and sent an embassy to Ava in 1385, offering to hold Pegu as a vassal state.
His proposal greatly resonated with the Ava court, which was dealing with a developing situation in Arakan: Saw Me, the latest Ava-nominated king, had been driven out. Ultimately, the Ava court, led by Chief Minister Min Yaza, assessed Pegu as an easier mission. Swa, who wanted to restore the erstwhile Pagan Empire, accepted Laukpya's proposal, touching off what would become "the forty years' war between Ava and Pegu."
First invasion (1385–1386)
Ava battle plan
King Swa and his court saw little difficulty in taking over Pegu. Their battle plan reflected that belief: Swa assigned his two young sons with no prior military experience—Crown Prince Tarabya, who was about to turn 17, and Prince Min Swe of Pyinzi, who had recently turned 12—to lead two relatively small armies. The king did appoint two of his best generals, including Thilawa of Yamethin and Theinkhathu of Sagu, to advise the princes. The plan called for a three-pronged attack. The first army led by the crown prince (9 regiments, 7,000 infantry, 500 cavalry, 20 war elephants) was to invade the Sittaung River valley from Toungoo. Prince Swe's second army (9 regiments, 6,000 infantry, 500 cavalry, 20 elephants) was to invade from Tharrawaddy along the Hlaing river, and join up with Laukpya's Myaungmya flotilla invading from the delta around Dagon (modern downtown Yangon) in a pincer movement towards Pegu.
Pegu battle plan
Pegu's battle plan was shaped by its sheer lack of manpower. A desperate Razadarit sent a last-minute mission to Donwun in search of levies but Sam Lek ignored the request. In the end, the Pegu command had no choice but to defend from a few key fortified towns en route to the capital. On the northeastern front along the Sittaung river, Hanthawaddy's main defenses began only at Fort Pankyaw (modern Waw), about 40 km (25 mi) northeast of Pegu. On the northwestern and western fronts, a series of smaller forts at Hlaing (modern Taikkyi), Hmawbi, and Dagon defended the route towards Pegu.
Invasion
Grinding advance
The invasion began in December 1385. Contrary to their expectations, both armies faced determined resistance from the start. On the northeastern front, Tarabya's army steadily advanced along the Sittaung until it reached Pankyaw. It laid siege to the fort but could not take it for weeks. On the northwestern front, Prince Min Swe's army ran into resistance much earlier at Hlaing (Taikkyi). It had to lay siege to the fort, and finally took the fort only after weeks of heavy fighting. The fall of Hlaing prompted Razadarit to come out of Pegu with an army to reinforce his defenses at Hmawbi. A vanguard regiment of the Ava's second army reached Hmawbi first but the regiment withdrew after its commander, Min Letwe of Pinle, fell in action. Soon after, Tarabya finally took Pankyaw after the fort's commander Nandameit fell in action. Laukpya now began sailing towards Dagon with his flotilla of war boats.
Chasing Razadarit
Tarabya's road to Pegu was now open. The crown prince assigned the Lord of Myede to guard Pankyaw, and marched towards Pegu. But when he learned that Razadarit had evacuated Pegu, Tarabya assessed that Razadarit had retreated to Dagon, and ordered all forces including those of Min Swe and Laukpya to converge around Dagon. It turned out to be a miscalculation. Razadarit had not retreated to Dagon, and was still outside of Pegu. When Ava forces marched on to Dagon, Razadarit swiftly marched to Pankyaw to cut off Ava's rear. The Ava command did not learn about Razadarit's siege of Pankyaw until their forces met up near Dagon. Both Ava armies now rushed back to Pankyaw, about 120 km (75 mi) from Dagon but by the time they got there, Pankyaw had just fallen to Razadarit's forces.
Ava forces now tried to corner Razadarit. Tarabya and his cavalry came face to face with Razadarit's main regiment outside Pankyaw, with the Hanthawaddy king himself leading the charge on his favorite war elephant. In the ensuing battle, a few of the Ava cavalry even got near the king's elephant and cut the elephant's tail but Razadarit managed to break through. Min Swe's army chased the Hanthawaddy king, and caught up with the king near a small town named Hsin. Tarabya ordered Min Swe to hold the position in the path of retreat, and not engage the enemy until his army could catch up. However, the 12-year-old prince was angered by his half-brother's order, and going against the advice of his commanders, ordered his troops to engage. His commanders reluctantly moved forward in a state of confusion. Razadarit's army broke through, and made it back to Pegu.
Withdrawal
The battle turned out to be the last of the campaign, which had already lasted more than five months. It was May 1386, and the rainy season was imminent. Tarabya was furious at both Min Swe, who had disobeyed his express order, and at Laukpya, who he thought had provided little help. Still, he was reluctant to return empty-handed; he discussed his options with his high command for another five days. In the end, Tarabya decided to withdraw for the rainy season, vowing to return after the rainy season. Laukpya and his flotilla, which had been lurking outside Dagon, also turned back.
First interlude (1386)
The rainy season saw competing diplomatic missions to Ava from both Pegu and Myaungmya. The Pegu mission arrived two months after the withdrawal (c. July 1386), bearing lavish gifts and a conciliatory letter directly addressed to King Swa Saw Ke from King Razadarit. Despite having survived the first invasion, the Hanthawaddy king had agreed to his court's recommendation to sue for peace with the more populous northern neighbor. In the letter, Razadarit, using respectful language—he addressed Swa, "Royal Paternal Elder Uncle"—asked the Ava king to honor the terms of the peace treaty Swa and his father signed back in 1370/71, and treat him with mercy.
In response, Laukpya hastily sent a delegation of his own to Ava to keep the alliance intact. In his letter to Swa, Laukpya humbly but also subtly pointed out that the failure of the campaign was due to a lack of coordination between the Ava armies, and that a better planned, coordinated campaign would certainly bring victory. After one month of deliberation, Swa and the court concluded that Pegu was still winnable outright. Swa rejected Razadarit's proposal, and planned to lead the next invasion by himself.
Second invasion (1386–1387)
Ava battle plan
The new battle plan differed from the previous plan in two key aspects. First, the invasion forces were now two and a half times larger. Swa had called up levies from around the kingdom, raising over 29,000 troops, including two Shan regiments. Secondly, the path of invasion for both the land and riverine forces would now be along the Irrawaddy front. The land army (11 regiments, 12,000 infantry, 600 cavalry, 40 elephants) commanded by Crown Prince Tarabya was to invade by land from Tharrawaddy. The riverine force (10 regiments, 17,000 troops, 100 transport boats/ships, 120 war boats) commanded by King Swa himself would attack the southern ports via the delta. Prince Min Swe was left out of the campaign; the prince was assigned to guard the capital Ava, with four regiments under his command. In preparation, the combined invasion forces met up in Prome (Pyay). Supplies had been shipped there as well. Then, Swa's riverine force then sailed down to a place called Ahlwe (near Myanaung). There, Laukpya's flotilla came up to join the riverine force.