Tugstumur Khan

Tugstumur Khan ascended the throne in 1378 during a tumultuous period between Mongolia and China. Tugstumur took the title Uskhal and instituted negotiations and military exercises to foster unity among the Mongolian provinces. Intent on increasing the size of his military, Tugstumur Uskhal recruited soldiers from Karakhorum and Incheon to prepare for operations in China.

The Chinese government also escalated their military preparations. In 1380 the Chinese sent soldiers to maneuver along the border and to penetrate into Mongolia. Under the guidance of general Mu-In, Chinese divisions invaded Mongolia. Light cavalry successfully occupied Karakhorum, ravaged several provinces, and took many Mongolians prisoner. At that time, Tugstumur Khan had based his center of operations in Incheon. He ordered Mongolian commanders Ulzibukh and Narbukh to attack Luleen in the eastern part of China's Khebei province, where they assassinated China's Lyu-Guan, a military commander of the Min state.

In 1381, the Min State retaliated. Under the leadership of commander Cyuie-Da, Chinese forces penetrated Chiphen. During the following six years (1382-1387), Mongolia and China rested from wartime antagonism and retribution, and the Min state maneuvered into position. In 1384 the Gaoli state submitted to the Min Empire and severed their diplomatic relations with Mongolia. Nagachug, a relative of Mukhulai (son-in-law or aristocrats), controlled numerous forces and occupied the land to intimidate the Gaoli state and maneuver into their territory.

The Min state was wary of possible unity between Tugstumur Khan and Nagachug. Min was concerned that such a unity could potentially overcome Min military forces. Therefore, Min decided to focus his efforts on the annihilation of Nagachug's armies. By 1387, the Min state had concentrated its forces in Lyaodun to destroy commander Nagachug's military forces in the Yuan state. In 1384, two thousand Chinese soldiers under the command of Phen Shen fought against Nagachug's armies; both sides suffered severe casualties. However, Chinese forces had succeeded in gaining better battlefield position, and Nagachug's armies, finding themselves in a hopeless situation, surrendered.

Subsequently, the Min state began to position its main forces against Tugstumur Khan. By the spring of 1388, Mongolia and Min engaged in a campaign that ended Tumgstumur's ambitions for control of Min China. Suffering a terrible defeat, Tugstumur Khan, his eldest son, associated dignitaries, and a few surviving soldiers were forced to retreat toward Kharkhorum. Tugstumur's second son was captured along with Tugstumur's leading minister and lords. In all, the Chinese took nearly three thousand people prisoner and over one hundred fifty thousand head of cattle as war prizes.

When Tugstumur Khan reached the Tuul River, he was attacked by Esunder, lord of the Argbukh origin. Conscious of the weakness in his military force, Tugstumur Khan set out to unite with the armies of commander Markhas. Unfortunately, a three-day snowstorm barred Tugstumur Khan's advance. Ultimately, Esunder dispatched a courier to capture Tugstumur Khan. The courier poisoned Tugstumur Khan in 1388.

• Uskhal Khan Tögüs Temür