Karnali Province is one of the seven federal provinces of Nepal formed by the new constitution, which was adopted on 20 September 2015. The total area of the province is 27,984 square kilometres (10,805 sq mi), making it the largest province in Nepal with 18.97% of the country's area. According to the 2011 Nepal census, the population of the province was 1,570,418, making it the least populous province in Nepal. The province borders the Tibet Autonomous Region of China to the north, Gandaki Province to the east, Sudurpashchim Province to the west, and Lumbini Province to the south. Birendranagar with a population of 154,886 is both the province's capital and largest city.

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.