He is best remembered in Burmese history for his epic struggles against King Razadarit of Hanthawaddy Pegu in the Forty Years' War (1385–1424).
While he ultimately failed to conquer Hanthawaddy and Launggyet Arakan, he was able to bring in most of cis-Salween Shan states to the Ava orbit.
The future king was born in a small village called Gazun-Nyeint (present-day northern Sagaing Region) on 13 September 1373.
[note 1] His father King Swa Saw Ke of Ava had met his commoner mother Saw Beza earlier in the year during a military campaign against Mohnyin.
[3][4] Chronicles say that after giving birth to the child, Beza showed up at the Ava palace to present the male son, as instructed to by the king.
The bullying became a serious problem, and in 1381/82, the king had to send away Swe and Theiddat to a small monastery near Pinle to study under the chief primate (Thinga-Yaza).
The two princes studied under the learned monk, and traveled around the region, including Taungdwingyi, Minbu, Ngape and Padein, with their attendants.
[6] The king kept Swe out of Tarabya's reach, and appointed his 11-year-old son governor of Pyinzi, a small town about 85 km southwest of Ava.
In 1385, the king ordered his two eldest sons to lead a two-pronged invasion of the southern kingdom in what would become known as the Forty Years' War.
Then, King Razadarit of Hanthawaddy made a tactical error by coming out of his fortified capital to attack Ava positions near Pankyaw.
Tarabya, the overall commander-in-chief, sent a messenger, ordering Swe to hold his position and not to engage Razadarit until his army could reach the scene.
When Tarabya became mentally unstable about five months into his reign, and other pretenders began circling the throne, Swe was not in a strong-enough position to challenge them.
[24] He also appointed Theiddat governor of Sagaing with the title of Thiri Zeya Thura but stopped short of declaring him his heir-apparent.
[24] While Sagaing was a sizable province that used to be an independent kingdom, the younger brother was never satisfied with the reward, and held a "lingering resentment that would later rear its ugly head".
[25] When the dry season began, Hanthawaddy forces invaded by the Irrawaddy river, attacking all the riverside towns and cities, including their main targets, Prome (Pyay) and Ava (Inwa).
Minkhaung bought time by sending a delegation led by a learned Buddhist monk, Shin Zawtayanta, to broker a truce.
The Ava army decisively defeated the invaders south of Prome on 26 December 1402, forcing Pegu to ask for terms about ten days after the battle.
In the following years, the king, with the advice of Min Yaza, resumed the expansionist policy of his father in order to restore the Pagan Empire.
According to the Burmese chronicles, the acquisition drive was largely peaceful, and accomplished through diplomatic missions led by Min Yaza to Onbaung (Hsipaw) in 1404/05, Nyaungshwe in 1405/06 and Mohnyin in 1406.
Using alleged Arakanese raids on Ava's western districts, he sent a 10,000-strong army led by his eldest son Minye Kyawswa to Arakan.
[36] The king then appointed Minye Kyawswa his heir apparent,[note 5] and married him to Saw Min Hla, a cousin of the groom.
[40] He broke the 1403 agreement: Pegu stopped sending the annual shipment of 30 elephants and Ava's share of customs revenue of the Bassein port.
[38] Meanwhile, Minkhaung tried to solidify his hold over Arakan by sending his eldest daughter Saw Pyei Chantha to be the wife of Anawrahta as well as a senior minister to aid the vassal king.
Over the next five years, Minkhaung would call on Minye Kyawswa to wage war against his enemies on multiple fronts: against Hanthawaddy in both Lower Burma and Arakan, and against Ming China and its vassal states in the north.
[54] (According to the Arakanese chronicle Rakhine Razawin Thit, Ava retained a toehold at the Khway-thin-taung garrison in northern Arakan until 1416/17.
[55] But Ava would not send a major force to Arakan, and the western state would remain a Hanthawaddy vassal at least until Razadarit's death.)
The powerful Shan state had been ordered by the Ming court to retaliate against Ava's annexation of Mohnyin six years earlier.
The attack was serious enough that Minkhaung himself marched with his army to relieve Prome, and ordered Minye Kyawswa to join him on the southern front.
They made no meaningful progress until when the Hanthawaddy command suddenly lost its two most senior generals: Gen. Byat Za (natural causes)[59] and Gen. Lagun Ein (KIA).
[23] One of his concubines, Saw Pan-Gon, gave birth to a daughter named Saw Nant-Tha, who was later married to his nephew Prince Min Nyo of Kale Kye-Taung.