The Newars are regarded as the original inhabitants of the Kathmandu Valley, but their origins are shrouded in mystery. They speak a Tibeto-Burmese language, which indicates they originated in the east, but their physical features range from distinctively Mongoloid, again suggesting to east, to Indo-Aryan, which of course points to India.
In balance, it seems most like that the Kathmandu valley has long been a cultural and racial melting pot, with people coming from both east and west. This fusion has resulted in the unique Newar culture that is responsible for the valley's superb art and architecture.
The Newar golden age peaked in the 17th century when the valley consisted of small city-states, and Nepal was a vitally important trading link between Tibet and the north Indian plains. the valley's visible history is inextricably entangled with the Malla kings. It was during their reign, particularly in the 1600's and 1700's, that many of the valley's finest temples and palaces were built. Competition between the cities was intense and an architectural innovation in one place, such as the erection of a column bearing a statue of the ruling king, would inevitably be copied in the other cities.
Sorting out who built what and when is considerably complicated by the fact that at any one time there was not just one Malla king. Each of the three city-states in the valley – Kathmandu, Patan and Bhaktapur – had its own.
The unification of Nepal in 1768 by Gorkha's king Prithvi Narayan Shah signaled the end of the Kathmandu Valley's fragmentation. Nepali, an Indo-European language spoken by the Khas of western Nepal. replaced Nepalbhasa as the country's language of administration.