Byattaba

Despite the king's trust in them, the brothers were contemplating a rebellion. The main instigator was Laukpya, who was posted far away from Martaban, and had quickly developed a network of support across the delta province through a series of alliances. The opening came in 1363. That year, the king asked Byattaba to guard the capital Martaban while the king and his retinue went on a months-long elephant hunting trip near the Siamese border.[5] The king, whose main title was Hsinbyushin ("Lord of the White Elephant"), had been searching for a white elephant, considered highly propitious by Burmese sovereigns, since the death of his first white elephant in 1354/55. The king believed that his victory over the Lan Na invasion of 1351–1352 was due to the luck brought by his white elephant.[5] The king and his sizable retinue, consisted of his key advisers, generals and 2000 troops, went on the planned hunting trip, c. November 1363. The king left the capital in the trusted hands of Byattaba, who in turn was aided by his brothers E Bya Bon and U-Lo.[6]

The brothers then staged a silent coup. Byattaba consolidated power at the palace. E Bya Bon took over the defenses of Lagun Byi, a town north of Martaban while U-Lo took over Moulmein (Mawlamyaing), the town immediately south of Martaban, across the Salween (Thanlwin). In the delta, Laukpya had fortified Myaungmya.[3] Only their half-brother Lagun, governor of a small eastern delta town of Let-Hlyit remained loyal to the king.[2] The king did not learn about the coup until four months into the trip. He rushed back to the capital. His troops recaptured Lagun Byi from E Bya Bon but twice failed to take Martaban, losing his two best generals in the process.[7] In the western theater, Laukpya tried to seize Dala–Twante but could not get past the defenses of his half-brother Lagun.[2]

By the rainy season of 1364, a stalemate had developed. The king had set up camp at Donwun, 100 km north of Martaban. Byattaba had held on Martaban and the southern coast but his hold was tenuous. In Martaban, Byattaba and E Bya Bon had had to institute a lockdown of the city to prevent people from fleeing.[note 3] With the king controlling the most populous Pegu province, the brothers realized that they could not hold out for long. They appealed to the king of Lan Na to intervene, promising a cut of the tax revenue of Martaban and Moulmein ports.[2][8]

At Chiang Mai, King Kue Na was interested.[9] Chiang Mai had wanted to pull Martaban, a former Sukhothai tributary, into its sphere of influence at least since 1351 while Chiang Mai's rival Ayutthaya had claimed all former Sukhothai tributaries since 1350.[note 4] When he heard that Chiang Mai might again invade, U repaired ties with Chiang Mai by sending his eldest daughter to Kue Na in a marriage of state. Although Chiang Mai's intervention did not materialize, U did not proceed to retake Martaban or the delta.[8][10]

An uneasy ceasefire persisted for the next five years. The brothers controlled nearly two out of the three provinces of the kingdom: Byattaba held the Martaban province, south of Donwun (modern Mon State and southern Kayin State) while Laukpya held the delta (modern Ayeyarwady Region). The king controlled only the northern third of the Martaban province to Donwun, and the all-important Pegu province (modern southern Bago Region and Yangon Region).[11]

The brothers then launched a surprise attack on Donwun in 1369. Their attack was opportunistic, and came a few days after the death of Chief Minister Pun-So, U's righthand man. During the mourning period, E Bya Bon and 700 warriors, disguised as mourners, managed to get inside Donwun, and seized U's palace. The king fled to Pegu (Bago), about 120 km northwest of Donwun, across the Bay of Martaban, and relocated his capital there.[12] (Although the move to Pegu was made under duress, the move proved permanent. By then, Pegu was the more natural location to be the capital due to its strategic location—between the other two provinces—and its "agricultural and demographic potential".[13] The traditional home of the dynasty, Martaban, on the other hand, was located on the upper Tenasserim coast, and too close to the Tai kingdoms to the east.[14])

The brothers' advantage was fleeting. They tried but neither Byattaba nor Laukpya could make any headway into Pegu throughout 1370–1371.[15] Meanwhile, U secured his rear by successfully negotiating a peace treaty with King Swa Saw Ke of Ava that demarcated the border between the two kingdoms.[15][16] Soon after the treaty with Ava, U launched a counterattack, which was partially successful. His forces retook Donwun but could not advance farther south. The two sides were now back on their pre-1369 borders.[17]

According to the Razadarit Ayedawbon, it was the king that first sued for peace with the rebel brothers.[18] Despite his success in retaking Donwun, he was still concerned about a potential interference by Lan Na. (The marriage alliance between the two states was at a breaking point. His daughter Tala Mi Thiri was never happy at Chiang Mai, and had been asking her father to bring her back for several years.)[18] The brothers too were interested in an agreement that would preserve their status. The two sides then agreed to a treaty that called for U to recognize the brothers as the rightful viceroys of Martaban and Bassein (Irrawaddy delta) provinces, and to pay them 10 viss (16.33 kg) of gold and ten elephants in exchange for the brothers' recognition of U as their sovereign as well as brokering of an agreement with Lan Na to maintain peace.[note 5] As the Razadarit Ayedawbon recounts, U realized the absurdity of the overlord paying tribute to the vassals but he ultimately decided to swallow his pride, and agreed to the terms.[19] On the other hand, Byattaba and Laukpya realized that they needed Lan Na's support in order to neutralize Pegu's stronger position. The brothers sent 15 viss (24.49 kg) of gold in total to retain Chiang Mai's support. The king of Lan Na sent back Tala Mi Thiri to Pegu.[19]

The treaty held until Binnya U's death in 1384. Though officially viceroys, Byattaba and Laukpya ruled their territories like sovereigns. For their part, they did not get involved in the affairs of Pegu even when the king gradually withdrew from governing due to his long illness. When U's 15-year-old son Binnya Nwe raised a rebellion in 1383, neither viceroy interfered. When princess-regent Maha Dewi asked them to contribute troops to put down the rebellion, each sent a regiment to ensure that the fighting would not spill over to their territories. But neither joined the actual fighting.[20][21]

In January 1384, the Pegu court chose the rebel son Nwe, who took the reign name of Razadarit.[22] Byattaba and Laukpya did not acknowledge the new king, who at his accession had not yet turned 16. It was not just them. Even rulers of the northern Martaban province who were loyal to the late king refused to acknowledge the new boy king. Razadarit for his part considered the entire "32 districts" of the Martaban province in revolt.[23] One silver lining was that not all the rebels were united. For example, Gov. Smim Than-Hlyit of Donwun, who fought against Byattaba in the 1360s, declared that he was not allied anyone.[23]

Byattaba and Laukpya too were not in sync as to how to respond to Razadarit. Laukpya believed that they needed external support to keep Pegu at bay. Laukpya's preferred external power was the northern Ava Kingdom,[24] which by the mid-1380s, had emerged as the main power in the Irrawaddy valley, and was intent on restoring the erstwhile Pagan Empire.[25][26] Byattaba, whose territory bordered the Tai states to the east, was much more circumspect about an alliance with Ava, and ultimately decided to stay neutral. Unlike Laukpya, he did not attack Pegu during the first two invasions of Pegu by Ava in 1385–1387. The fighting took place almost entirely in the delta.[24]

Byattaba's decision would come back and haunt him. In 1387, after two failed invasions, Ava had to pause its war in the south as it was pulled into a renewed conflict with the northern Shan state of Maw.[27] Razadarit immediately seized the opportunity, and sent a sizeable army to Martaban in the dry season of 1387–1388. Much of the fighting took place in the northern parts of the province. It took several months before the Pegu army could breach the defenses of Donwun. Than-Hlyit and his 300 troops tried to flee to Martaban but the governor-general was killed en route by the Pegu troops.[28]

The way to Martaban was now open. Unlike before, Laukpya had not opened the western front. But Byattaba did not panic. He still had the support of his other brothers, E Bya Bon and U-Lo, who were commanders in his army, and had collected enough men and arms. When the Martaban command heard that a Pegu army was taking a circuitous route through the woods to encircle the city from the east, the brothers planned a surprise attack outside the city. In the wee hours, the Martaban army, led by the three brothers themselves, ambushed and destroyed the five vanguard regiments of the Pegu army. But the Martaban command did not know that two Pegu rearguard regiments, led by generals Smim Than-Byat and Dein, were still in the area. While the Martaban army dispersed to mop up the remaining enemies in the area, Than-Byat launched a surprise attack targeting the battalions guarding the Martaban command. It worked. Byattaba, E Bya Bon and U-Lo all fled. The remaining Martaban forces surrendered.[29][30]