By 55,000 years ago, the first modern humans had arrived on the Indian subcontinent from Africa, where they had earlier evolved.[31][32][33] The earliest known modern human remains in South Asia date to about 30,000 years ago.[34] The oldest discovered archaeological evidence of human settlements in Nepal dates to around the same time
After 6500 BCE, evidence for domestication of food crops and animals, construction of permanent structures, and storage of agricultural surplus appeared in Mehrgarh and other sites in what is now Balochistan.[36] These gradually developed into the Indus Valley Civilization,[37][36] the first urban culture in South Asia.[38] Prehistoric sites of palaeolithic, mesolithic and neolithic origins have been discovered in the Siwalik hills of Dang district.[39] The earliest inhabitants of modern Nepal and adjoining areas are believed to be people from the Indus Valley Civilization. It is possible that the Dravidian people whose history predates the onset of the Bronze Age in the Indian subcontinent (around 6300 BCE) inhabited the area before the arrival of other ethnic groups like the Tibeto-Burmans and Indo-Aryans from across the border.[40] By 4000 BCE, the Tibeto-Burmese people had reached Nepal either directly across the Himalayas from Tibet or via Myanmar and north-east India or both.[41] Another possibility for the first people to have inhabited Nepal are the Kusunda people. According to Hogdson (1847), the earliest inhabitants of Nepal were perhaps the Kusunda people, probably of proto-Australoid origin.[42] Stella Kramrisch (1964) mentions a substratum of a race of pre-Dravidians and Dravidians, who were in Nepal even before the Newars, who formed the majority of the ancient inhabitants of the valley of Kathmandu.[43]
By the late Vedic period, Nepal was being mentioned in various Hindu texts, such as the late Vedic Atharvaveda Pariśiṣṭa and in the post-Vedic Atharvashirsha Upanishad.[44] The Gopal Bansa was the oldest dynasty to be mentioned in various texts as the earliest rulers of the central Himalayan kingdom known by the name 'Nepal'.[45] The Gopalas were followed by Kiratas who ruled for over 16 centuries by some accounts.[46] According to the Mahabharata, the then Kirata king went to take part in the Battle of Kurukshetra. In the south-eastern region, Janakpurdham was the capital of the prosperous kingdom of Videha or Mithila, that extended down to the Ganges, and home to King Janaka and his daughter, Sita.