After the Anglo-Bhutan War in 1864, the Treaty of Sinchula (1865) was signed, in which Bhutanese held territory east of the Teesta River was ceded to the British East India Company. At that time, Kalimpong was a hamlet, with only two or three families known to reside there. The first recorded mention of the town was a fleeting reference made that year by Ashley Eden, a government official with the Bengal Civil Service. Kalimpong was added to district of Darjeeling in 1866. In 1866–1867 an Anglo-Bhutanese commission demarcated the common boundaries between the two, thereby giving shape to the Kalimpong subdivision and the Darjeeling district.