In 1368, after the downfall of the Yuan Dynasty, the Mongolian forces retreated to the Mongolian plateau, known as the Northern Yuan Dynasty historically. Afterwards, Mongolia went through a power struggle and gradually divided into three main regions: Monan Mongolia, Mobei Mongolia, and Moxi Mongolia.

- Monan Mongolia, which includes modern-day Inner Mongolia, consists of the Horqin, Chahar, Tumed, and Urad tribes.

- Mobei Mongolia, which is equivalent to present-day Outer Mongolia or Khalkha Mongolia, comprises the Chechen Khan, Tuxiet Khan, Sanyin Nuoyan Khan, and Zasaktu Khan.

- Moxi Mongolia, which corresponds to Xinjiang and parts of Central Asia, is also known as Oirat Mongolia and Oala, including Junggar, Heshuote, Turhut, and Durbert.

During this period, the Ming and Qing dynasties effortlessly exploited the ongoing conflicts among the diverse Mongolian tribes, taking advantage of their internal divisions.

The Demise of the Mongolian Empire

During the Ming Dynasty, Wala posed a potential threat to the northern border. Ming Yingzong was captured in the battle of Tumubao, which resulted in the loss of dignity for the Ming Dynasty. In the Qing Dynasty, the rulers exploited the divisions among the Mongolian tribes and implemented a pro-Mongol policy. As a result, Monan Mongolia and Mobei Mongolia surrendered to the Qing Dynasty at its inception.

The most challenging entity is Moxi Mongolia, specifically Oirat Mongolia during the Ming Dynasty, and Oirat Mongolia and Erut Mongolia during the Qing Dynasty.

Gushi Khan helped to found Ganden Phodrang Dynasty 

There are four main tribes in Oirat Mongolia: the Junggar, Durbert, Turghut, and Khoshut tribes. The Oirat Mongols later migrated westward to Qinghai and the Western Regions. Gushi Khan of the Khoshut tribe unified the Qinghai-Tibet Plateau in 1637 and established the Khoshut Khanate. However, the Heshuote Khanate was later destroyed by the Junggar tribe, who established the Junggar Khanate with the aim of unifying all Mongolian forces. After several campaigns led by Kangxi, the Qing Dynasty ultimately defeated and destroyed the Junggar Khanate. Thus, in the centuries-long conflict between Mongolia and the Jurchens, the Jurchens emerged as the ultimate victors.

Among the forces in Mongolia after the fall of the Yuan Dynasty, Gushi Khan, the founder of the Heshuote Khanate, emerged as a hero. Gushi Khan is the descendant of Hasar, the younger brother of Genghis Khan. In his youth, he rode alone to resolve the conflict between Oirat Mongolia and Khalkha Mongolia. The Chinese bestowed upon him the title of "Great National Teacher," which translates to Gushi. In the 17th century, he succeeded as the leader of the Heshuote tribe and Oirat Mongolia and came to be known as Gushri Khan.

In 1641, Gushi Khan conquered the Tsang region, overthrowing the Desi Tsangpa Khan regime and gaining control of Tibet. He allied with the Gelug Sect and established his authority over the Qinghai-Tibet local government. Five years later, Gushi Khan submitted to the fifth Dalai Lama. However, the Khoshut Khanate later faced a growing threat from the Dzungar tribe.

Lazang Khan's final fight with Junggaar Khanate 

The Khoshut Khanate was ultimately destroyed by the Junggar Khanate, resulting in the demise of Lazang Khan, the last Great Khan. Despite his role as a ruler who subdued others, Lazang Khan displayed exceptional military prowess.

Tsangyang Gyatso, the sixth Dalai Lama, is a renowned poet. Despite being overthrown by Lazang Khan in the political conflict on the Qinghai-Tibet Plateau, Tsangyang Gyatso gained significant recognition in the literary sphere.

Rising the power of the Qing Dynasty 

After the Ming Dynasty's collapse, the Jurchens grew stronger. Concurrently, the Mongolian tribes on the Mongolian Plateau faced the Eastern Jurchens' threat. To gain control over Mongolia, the Jurchens implemented a policy of intermarriage between the Manchu and Mongolian peoples.

Nurhachi, Huang Taiji, and Shunzhi all married Mongols. The Empress Dowager Xiaozhuang, known to us, belongs to the Horqin tribe of Mongolia, which is descended from Hasaer. After receiving the help of Horqin Mongolia, Huang Taiji was able to successfully conquer Mongolia and enter the Central Plains.

The final Khan of the Mongolian Empire was Lin Dan Khan, who was in a nominal co-lord position. The Mongolian ministries had long been engaged in power struggles and refused to follow Lin Dan Khan, particularly Moxi Mongolia, on behalf of the emperor. Lin Dan Khan was defeated by Huang Taiji in 1632 and escaped to Qinghai. He died in 1634, leading to the demise of the nominal Mongolian Empire.

Arising of Khoshut Khanate

Among Genghis Khan's brothers, the most famous one is Hasar. Not only was Hasar his right-hand man during Genghis Khan's campaigns in the North and South, but he was also exceptionally heroic. Moreover, the descendants of Hasar are known for their talent. In fact, it was due to the assistance of Hasar's descendants that the Jurchens were able to overthrow the descendants of Genghis Khan.

Moxi Mongolia, also known as Oirat Mongolia, grew stronger in the Western Regions. In 1634, the Gelug Sect of Tibet sought assistance from the leader of Oirat Mongolia, Gushri Khan, to attack Desi Tsangpa Khan. In 1635, Gushi Khan marched into Qinghai and gained control of the entire territory. By 1640, they advanced into Kham, followed by Tibet in 1641, ultimately overthrowing Desi Tsangpa Khan's regime in 1642.  

Gaining the Power by Lazang Khan

After the death of Gushri Khan, Dayan Ezir Khan, Dalai Khan and Lazang Khan became the ruler of the Khoshut Khanate. Lazang Khan was the final great Khan of the Khoshut Khanate. In fact, Lazang Khan has been engaged in a power struggle since assuming the throne. "The Complete Biography of Tsangyang Gyatso's Poems" provides a comprehensive account of Lazang Khan's life, with particular emphasis on the significant influence of Sangye Gyatso.

After Tenzin Dalai Khan's death, Lazang Khan's elder brother should have taken the throne. Instead, Lazang Khan killed his brother and assumed the role himself. This indicates that Lhazang Khan orchestrated a coup, similar to the style of Fu Jian and Li Shimin. It shows that he was not weak or incompetent.

The Power struggle between Lazang Khan and Deba Sangye Gyatso

After ascending the throne, he engaged in a power struggle with Desi Sangye Gyatso. In 1679, Sangye Gyatso officially assumed the position of the fifth Diba, which is the Tibetan equivalent of the prime minister in the Ganden Phodrang dynasty. Consequently, Sangye Gyatso held the second highest position, subordinate only to the fifth Dalai Lama.

During the period of the Khoshut Khanate, the Qinghai-Tibet Plateau was under the rule of the Khan and Dalai Lama's Ganden Phodrang. Sangye Gyatso, known for his skilful manipulation of power, formed an alliance with Galdan of the Junggar tribe. Their plan was to bring the Junggar tribe into Tibet and forcefully remove Lhazang Khan from power. However, Emperor Kangxi was engaged in a military conflict with Galdan during that time, referred to as the three campaigns against Galdan.

In 1697, Kangxi successfully defeated Galdan for the third time, resulting in Galdan's death in Kebuduo. With Galdan gone, Sangye Gyatso was left without any allies. Meanwhile, Lazang Khan's cavalry defeated Sangye Gyatso, leading to his capture.

The fifth Dalai Lama died 15 years ago, but Sangye Gyatso, known as Dessi, kept it a secret. He wanted to exploit the Dalai Lama's name to gain power over the Gelug Sect of the Khalkha tribe in Mongolia. Galdan, who is also a follower of the fifth Dalai Lama, is unaware of his death. Galdan and Sangye Gyatso share a brotherly bond. However, Galdan has recently been defeated by Kangxi, while Lhazang Khan has defeated Sangye Gyatso. 

Political Turmoil in Tibet After Desi Sangye Gyatso's Death

In 1705, Lhazang Khan killed Sangye Gyatso and simultaneously deposed the sixth Dalai Lama, Tsangyang Gyatso, whom he had installed. Tsangyang Gyatso, the most innocent in this power struggle, fell victim to it. In 1697, Sangye Gyatso presided over Tsangyang Gyatso's enthronement ceremony, but he still held the true power. The fifth Dalai Lama passed away over a decade ago. His decision to conceal this fact and not report it was a ploy to entice the Dzungar tribe into Tibet, expel Lhazang Khan from the Khan system, and secure control of Tibet's power.

Tsangyang Gyatso died in 1706 during his escort to the capital, leaving behind timeless poems. Lazang Khan also perished in a power struggle. As a result, the Dzungar tribe gained strength and sought to unify the Mongolian tribes. In 1717, after the defeat of Galdan, the Dzungar tribe invaded Qinghai Tibet once more. Lhazang Khan met his demise during this invasion, leading to the downfall of the Khoshut Khanate.

Death of Lazang Khan

However, the Dzungar Khanate did not ultimately emerge triumphant. The downfall of Lazang Khan presented an opening. In 1720, Kangxi dispatched soldiers to Tibet. Yinti, the emperor's fourteenth son, assumed the role of Fuyuan's general and accompanied the new Dalai Lama to Tibet for his enthronement as the seventh Dalai Lama. General Dingxi Garbi commanded the South Route Army, while Yue Zhongqi led the offensive. Together, they vanquished the invading Junggar army through two strategic flanking manoeuvres.

In the end, the Qing Dynasty expelled the Mongolian army of the Dzungar tribe and abolished the Diba system. In 1728, the system of Amban stationed in Tibet was formally established. 
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