At least three waves of Nepalese diaspora can be identified. The earliest wave dates back to hundreds of years as early marriage and high birthrates propelled Hindu settlement eastward across Nepal, then into Sikkim and Bhutan. A backlash developed in the 1980s as Bhutan's political elites realized that Bhutanese Buddhists were at risk of becoming a minority in their own country. At least 60,000 ethnic Nepalese from Bhutan have been resettled in the United States. A second wave was driven by British recruitment of mercenary soldiers beginning around 1815 and resettlement after retirement in the British Isles and Southeast Asia. The third wave began in the 1970s as land shortages intensified and the pool of educated labor greatly exceeded job openings in Nepal. Job-related emigration created Nepalese enclaves in India, the wealthier countries of the Middle East, Europe, and North America. Current estimates of the number of Nepalese living outside Nepal range well up into the millions.