The history of Sikkim begins with ancient Hindu and Tibetan contacts, followed by the establishment of a Tibetan kingdom (Chogyal) in the 17th century. Sikkim emerged as a polity in its own right against a backdrop of incursions from Tibet and Bhutan, during which the kingdom enjoyed varying degrees of independence. In the early 18th century, the British Empire sought to establish trade routes with Tibet, leading Sikkim to fall under British suzerainty until independence in 1947. Initially, Sikkim remained an independent monarchy, however in 1975, its subjects voted by plebiscite to become a state of India.