History of Sikkim reflects the past of the territory of Sikkim. Sikkim has a rich past that sings the praise of the past events and kingdoms that ruled in the territory of Sikkim.
Although much is not known about the ancient history in Sikkim, it is evident that three tribes namely, Naong, Mon and Chang resided within the territory of Sikkim. But, these tribes could not retain their dominance over Sikkim for long; the Lepchas replaced the aforesaid tribes soon after they entered the territory of Sikkim.
The coming of the Lepchas and their settlement and combat with the aborigines of Sikkim constitutes a major part of the early Sikkim history. But, the modern history of Sikkim is said to have begun in 1641.