The Treaty of Sugauli (also sometimes spelled as Seaguli) was signed in 1816 between the East India Company and Nepal following the Anglo-Nepalese War (1814-1816).
This important treaty established formal relations between British India and Nepal and had several significant outcomes:
It defined the boundaries between British India and Nepal
Nepal ceded approximately one-third of its territory to the British
Nepal agreed to allow a British Resident in Kathmandu
Nepal surrendered territories in the Terai region, parts of Sikkim, and lands in the western hills
The treaty established Nepal as a sovereign nation but effectively made it a semi-protected state under British influence
