The commander led the military's vanguard land and naval forces as well as notable assassination missions against the enemies of his lord King Razadarit.
He is best remembered in Burmese history for his battles against the northern Ava Kingdom in the Forty Years' War as well as his bravery and honesty.
Lagun Ein was mortally wounded and captured by the Ava navy in the first battle after he was promoted to the rank of general.
He had gained the deep respect of the Ava high command, which sent his body on a raft down the Irrawaddy with full military honors.
Chronicles provide no information about his early life except that his personal name was Ma Than-Lon (မသံလုံ, Burmese pronunciation: [maʔ θàɴ lòʊ̯ɴ]).
[1] At any rate, Than-Lon took part in King Razadarit campaign against the Martaban province (present-day Mon State and southeastern Bago Region.)
[2] Impressed, the king ordered him to lead a mission to assassinate Ma Gyaing, governor of nearby Thanmaung town.
[5] After a brutal campaign that left the conquered region starving and ravaged,[5] the victorious king handed out lavish awards and fiefdoms to his key officers.
The Hanthawaddy command then devised a plan to lure the Bassein navy out of their entrenched position to an area downstream at Pan-Hlaing.
When his superiors reluctantly reported the predicament to the king, Razadarit ultimately decided that he needed Lagun Ein more than his queen.
The Razadarit Ayedawbon chronicle reports one incident in which Byat Za was displeased with Lagun Ein's performance.
[27] The two armies met near the Thaymathauk (or Thawutti) village, and Lagun Ein's vanguard force engaged the enemy.
[27] The remaining Hanthawaddy regiments led by Byat Za did not lose nerve, and met the Ava army the next day.
But Byat Za was extremely displeased with the performance of his vanguard units, and felt that Lagun Ein in particular should review the parts that went wrong, and not bask in glory.
But Lagun Ein strongly defended by stating that he engaged the enemy exactly as the battle plan called for, and that it was other vanguard units that did not follow his lead.
[28] The king largely stayed neutral, just issuing a mild reprimand to Lagun Ein for his non-courtly "country-style" blunt speech.
Lagun Ein was the lowest ranking member of the 30-member Hanthawaddy delegation led by Byat Za to negotiate the ceasefire terms with their Ava counterparts, and to set up a meeting between the two kings.
Lagun Ein answered that he wanted to win justly, not through manipulation and misrepresentation, and that he was never comfortable with the plan, and could not bear to lie.
Lagun Ein and his men took Minkhaung's ruby-studded royal sword and gold-plated betel nut chest.
When they got back, Saw Pyei Chantha, Minkhaung's daughter who had been captured in early 1408 and put in Razadarit's harem, identified that the sword and the chest were her father's.
Ava forces led by Crown Prince Minye Kyawswa had been trying to break the siege by attacking the Hanthawaddy army from the outside.
[39][40][41] Razadarit was greatly shaken by the deaths of Lagun Ein and Byat Za, and ordered an immediate withdrawal from Prome.