The unification of Nepal was the process of building the modern Nepalese state, from fractured petty kingdoms including the Baise Rajya and the Chaubisi Rajya, which began in 1743 AD. The prominent figure in the unification campaign was Prithvi Narayan Shah, King of Gorkha. On 25 September 1768, he officially announced the creation of the Kingdom of Nepal and moved his capital from Gorkha to the city of Kathmandu.

Nepali is an Indo-Aryan language native to the Himalayas region of South Asia. It is the official, and most widely spoken, language of Nepal, where it also serves as a lingua franca. Nepali has official status in the Indian state of Sikkim and in the Gorkhaland Territorial Administration of West Bengal. It is spoken by about a quarter of Bhutan's population. Nepali also has a significant number of speakers in the states of Arunachal Pradesh, Assam, Himachal Pradesh, Manipur, Meghalaya, Mizoram and Uttarakhand. In Myanmar it is spoken by the Burmese Gurkhas. The Nepali diaspora in the Middle East, Brunei, Australia and worldwide also use the language. Nepali is spoken by approximately 19 million native speakers and another 14 million as a second language.