One of the earliest treaties regarding the boundaries in the western sector was signed in 1842. Ladakh was conquered a few years earlier by the armies of Raja Gulab Singh (Dogra) under the suzerainty of the Sikh Empire. Following an unsuccessful campaign into Tibet in 1840, Gulab Singh and the Tibetans signed a treaty, agreeing to stick to the "old, established frontiers", which were left unspecified. The British defeat of the Sikhs in 1846 resulted in the transfer of the Jammu and Kashmir region including Ladakh to the British, who then installed Gulab Singh as the Maharaja under their suzerainty. British commissioners contacted Chinese officials to negotiate the border, who did not show any interest. The British boundary commissioners fixed the southern end of the boundary at Pangong Lake, but regarded the area north of it as "terra incognita".