Biligtü Khan Ayushiridara

Biligtü Khan, born Ayushiridara (Билигт хаан Аюушридар) (temple name: 昭宗, Zhaozong; r. 1370–1378), was a ruler of the Northern Yuan Dynasty in Mongolia. Ascended to the throne after the death of his father who was the last Yuan emperor, he defeated the invading Ming army in 1372 and recaptured some Chinese borderlands that were previously lost to the newly founded Ming Dynasty.

Early life
Ayushiridara was the eldest son of Toghun Temür Khan and Öljei Khutughu Khatun in 1338. He was given his earliest tuition in Chinese at the house of his father's minister, Toqto'a, at age ten. Toghun Temür's principal empress, Danashri, bore only one son who died in infancy. The Mongol noyans mostly preferred another Borjigin (Mongol noble) heir, rather than Ayushiridara, as his mother was a former palace maid and tea server of Korean nationality. Only after the purge of Danashri's family and the death of Bayan of the Merkid, he and his mother were accepted at the Mongolian court. Induced by his Korean empress, Öljei Khutughu, the Yuan Emperor Toghun Temür scheduled to elect his heir apparent in 1353. However, Toghtogha delayed the schedule for some unknown reason. This aroused the anger of the latter's political enemies. The chief minister and his former protégé, Hama, and Ayushiridara, with the support of the empress Öljei Khutughu, accused him of corruption and violation of law while he was fighting the Red Turban Rebellion in 1354. This situation halted Toghtogha who was successful in defeating the rebellion and was stripped of his dignities and sent to Hoai-nan into exile.

Hama was made first minister and all power was then in his hands. Elated by this success, Hama decided to raise to the throne Ayushiridara. This plot was discovered, Hama was sentenced to exile and strangled by his enemies there in 1356, and Ayushiridara was pardoned. When he became crown prince in 1353, it caused internal strife between his supporters and opponents. Seven years later the heir and Öljei Khutughu wished the first minister, Tai ping, should prevail on the Khagan to resign and leave him dominion. When Tai ping refused, they had poisoned the minister's partisans and forced him to resign. Power passed to a eunuch, Papuhwa, and to Cho sekin, two weak men. An opposition leader Bolad-Temür occupied the capital in 1364. Ayushiridara was ordered back by his father to Dadu. Feeling himself not powerful enough to resist Bolad-Temür's large army, Ayushiridara fled to the Yuan general, Köke Temür. When Bolad-Temür learned that Ayushiridara was advancing with troops, he arrested Öljei Khutughu and forced her to recall her son to the capital. However, Bolad-Temür's commanders deserted to Köke Temür. Toghun Temür secretly ordered Ho chang, son of the prince of Wei chun, to murder Bolad-Temür. After the latter's death, Köke Temür defeated Bolad-Temür's commander Tukiel in 1365. Ayushiridara forced Köke Temür to persuade the Emperor to resign in his favor. The Emperor was unwilling to abdicate, but he appointed his son lieutenant in the Yuan. Köke Temür tried to prevent it, but failed and was stripped of his dignities.

In 1368 the Yuan Dynasty was overthrown by the Ming Dynasty, and Toghun Temür Khan and his family fled north to Shangdu from Dadu. In 1370 Toghun Temür died in Yingchang. The Ming army captured the city and relatives and Maidarbal, a son of Ayushiridara who escaped safely to Karakorum where he was officially enthroned as Khagan of the Mongols with the Mongolian title of Biligtü (Intelligent).

Reign
Shortly after the succession, he fled to Karakorum and he changed the era name to Xuanguang (宣光, 1371–1378) there. Biligtü Khan made Köke Temür his commander in chief and chingsang of the right hand of the Central Government. The Yuan remnants in Mongolia, known as the Northern Yuan, still remained overall a strong power during his reign. Its dominions covered the areas from Northeast China to Xinjiang.

Hongwu Emperor demanded Biligtü Khan Ayushiridara to gave up his arms several times but failed. In 1372, the former dispatched the Ming army of 150,000 men to Mongolia. Biligtü Khan sent Köke Temür's army against the central division of the Ming army under Syu Dai. Syu Dai's troops reached Tuul River within 20 days. However, they were routed and their commander barely escaped with a few of his men. The eastern division of the Ming army advanced to Kherlen River, pillaging the Mongolian camps en route. They were suddenly defeated and forced to retreat to Orkhon where another bloody battle insued. After that they fought the Mongol army under Halajchani and was finally defeated near Karakorum. The western division of the Ming army was forced to retreat due to other divisions' failures, though, they won a series of places.

Ayushiridara asked the assistance from the Yuan's former vassal King Gongmin of Goryeo to fight against the Ming Dynasty of China. In his letter to Gongmin, Biligtü Khan says:

"...Oh wang, you are a descendant of Genghis Khan same as me. Therefore, we wish you to work with us to establish justice and truth under the heaven..."

On the contrary, King Gongmin refused to help and started an opposition policy against the Mongols, and retook their lands, which were annexed by the Yuan Dynasty in the 1270s. The pro-Mongol faction under Yin Im-in killed Gongmin in 1374. They sent envoys to the Mongols in Liaoyang and Biligtü Khan quickly recognized the legitimacy of King U, puppet of Yin Im-in. Biligtü Khan asked Goryeo Korea to send troops for a joint attack against the Ming fortress. The Goryeo court cautiously refused to help again.

The Mongols conquered Funin and Suijin districts in Sinhe, Liaoning and Hebei provinces in 1373, cutting the Ming from Liadong. In 1375, Nahacu, a Mongol official in Liaoyang province invaded the Liaodong Peninsula with aims of restoring the Mongols to power and succeeded with the support of the pro-Mongol Jurchens. The Ming ceased its raids into the Northern Yuan. Biligtü Khan's greatest general, Köke Temür, died in 1375. Biligtü Khan Ayushiridaraa also died in 1378 and his brother (or son), Tögüs Temür, succeeded to the throne.