The Anglo-Nepalese War (1 November 1814 – 4 March 1816), also known as the Gorkha War, was fought between the Gorkhali army of the Kingdom of Nepal (present-day Nepal) and the British forces of the East India Company (EIC, present-day India).
Both sides had ambitious expansion plans for the mountainous north of the Indian Subcontinent.
The war ended with the signing of the Sugauli Treaty in 1816, which ceded some of the Nepalese-controlled territories to the EIC.
The Treaty of Sugauli was ratified on 4 March 1816. As per the treaty, Nepal lost all of Sikkim (including Darjeeling), the territories of Kumaon and Garhwal and Western Terai.
The Mechi River became the new eastern border and the Mahakali river the western boundary of the kingdom.
Economic reasons constituted the major cause of the conflict with Nepal. The British had made constant efforts to persuade the Nepalese government to allow them trade access to fabled Tibet through Nepal.
Despite a series of delegations headed by William Kirkpatrick (1792), Maulvi Abdul Qader (1795), and later William O. Knox (1801), the Nepalese Durbar refused to budge an inch.
The British war effort was led by the East India Company and supported by a coalition of native states (the Garhwal Kingdom, the Patiala State and the Kingdom of Sikkim) against the Kingdom of Gorkha.
Most of the Kingdom of Gorkha’s war effort was led by the two Thapa families: the Thapa dynasty and the family of Amar Singh Thapa.