Was Sikkim ever a part of China's territory during the Yuan Dynasty, Ming Dynasty, Qing Dynasty and Republic of China?

Historically, Sikkim was once the territory of China, and has long been a subordinate country of Tibet. Sikkim is now occupied by India. In China's ancient books, ancient Sikkim was named Dremojong. Nepalese people moved here and called it a "new place", while early Tibetan immigrants called it a trip to Xinjiang, which means rice. As early as the 7th century, Zhe Mengxiong was a part of Tibet. In the 9th century, Zhemengxiong became an independent tribe, but the monasteries in its territory still belonged to the major monasteries in Tibet.

There are many myths circulating in Sikkim, but there are not many historical records before the establishment of hereditary monarchy. Sikkim used to be the residence of Leibucha people, most of whom lived on the southern slope of the Himalayas.