In 1947 and 1948, a popular vote for Sikkim to join newly independent India failed and Indian Prime Minister Jawaharlal Nehru agreed to a special protectorate status for Sikkim. Sikkim agreed to be a protectorate nation and Indian troops were allowed to man its borders, including Nathu La. During this period, more than 1,000 mules and 700 people were involved in cross-border trade through Nathu La. In 1949, when the Tibetan government expelled the Chinese living there, most of the displaced Chinese returned home through the Nathu La-Sikkim-Kolkata route.