The modern history of Nepal begins with Prithvi Narayan Shah who conquered various principalities into a single administrative unit during the latter part of the eighteenth century. The Ranas allowed the British to recruit soldiers during the first and second world wars, and the British showed their appreciation by formally recognizing Nepal as an independent state in 1923. In 1950, the Nepali Congress (NC) party, which was formed by merging the Nepali National Congress and Nepal Democratic Congress, launched an armed rebellion to oust the Ranas. In 1978, the Communist Party of Nepal (CPN) was established. The Nepal Sadhvawana Party (NSP) was formed in 1990 to represent the interests of Madhesi people. When Nepal began receiving foreign aid, the United States provided technical assistance in agriculture, health, mining, education, and malaria eradication. In 2006, Nepal emerged from a decade-long Maoist insurgency and 240 years of monarchy.