Fearing Russian military intervention into Tibet, in 1904 the British Raj made a military incursion into Tibet led by Francis Younghusband. Sometimes known as the "Mission to Lhasa", this was largely instigated by Lord Curzon, the Viceroy of India. The ensuing 1904 treaty and 1906 convention formalised Chinese suzerainty over Tibet while declaring that it would permit no foreign interventions (including by Russia or Britain). In 1910 China invaded Tibet and to escape the savagery the Dalai Lama fled to Sikkim, where he was sheltered by the British. Sikkim, sandwiched between India and Tibet, was under firm British protection and was only nominally an independent state.