Bhutan is a small, landlocked kingdom in South Asia. The Himalayan country was never formally colonized and, in the late 20th century, its history of isolationism began to give way to a gradual democratization which culminated in the creation of a multiparty democracy in 2008. Currently, Bhutan is a constitutional monarchy with the House of Wangchuck inhabiting the throne. Sitting on the ancient Silk Road, it borders Tibet to the north and northwest and India to the southwest, south and east. Spanning an area of 38,394 square kilometers (14,824 square miles), the majority Buddhist country is made up of three major ethnic groups, including the Bhutia, the Sharchop and the Nepalese. Bhutan has a remarkably diverse topography. In the south, its grassy, humid and forested Duars plains define the country's border with the Indian states of Assam and West Bengal. North of the plains, the terrain increases in elevation to form the lesser Himalayas which contain fertile valleys such as the Paro and Thimpu. Even further north, the land continues its upward slope until it culminates in the lofty peaks of the Himalayas which straddle the country's poorly demarcated border with China. Bhutan's geographic challenge as a small nation is to maintain its sovereignty in its territory squeezed between India and China. India views Bhutan as vital to its strategic defense and has historically served as Bhutan's dominant political, economic and security partner. China, on the other hand, has an ongoing border dispute with Bhutan. The 269 square kilometers of disputed territory crucially include the Doklam Plateau, which overlooks the Chumbi Valley and Beijing wants to possess to redress its military disadvantage against India in the region. India, which has its own border dispute with China, aims to prevent Beijing from resolving the dispute in its favor.