History Although its early history is vague, Bhutan seems to have existed as a political entity for many centuries. At the beginning of the 16th century, it was ruled by a dual monarchy consisting of a Dharma Raja, or spiritual ruler, and a Deb Raja, or temporal ruler. For much of its early history the Deb Raja held little real power, as the provincial governors (ponlops) became quite strong. In 1720 the Chinese invaded Tibet and established suzerainty over Bhutan. Friction between Bhutan and Indian Bengal culminated in a Bhutanese invasion of Cooch Behar in 1772, followed by a British incursion into Bhutan, but the Tibetan lama’s intercession with the governor-general of British India improved relations.