China has a population of over 1.3 billion people and covers an area of 3.7 million square miles. It has been led by the Communist Party since the founding of the People's Republic of China in 1949. Mandarin Chinese is the most widely spoken language. China's foreign policy has evolved over four main historical periods: ancient empires until 1840, a period of humiliation from 1840-1940 during Western incursions, the era of Maoism from 1945-1976, and a current phase of modernization since 1976. Mao interpreted Marxist and Leninist theories through the lens of China's own history when formulating foreign policy during his rule.