Explanation:

The predominantly mountainous region comprising the present day Himachal Pradesh has been inhabited since pre-historic times having witnessed multiple waves of human migration from other areas. Through its history, the region was mostly ruled by local kingdoms some of which accepted suzerainty of larger empires. Prior to India's independence from the British, Himachal comprised the hilly regions of Punjab Province of British India. After independence, many of the hilly territories were organised as the Chief Commissioner's province of Himachal Pradesh which later became a union territory. In 1966, hilly areas of neighbouring Punjab state were merged into Himachal and it was ultimately granted full statehood in 1971.