China–India relations major economies in the world. Growth in diplomatic and economic influence has increased the significance of their bilateral relationship. Cultural and economic relations between China and India date back to ancient times. The Silk Road not only served as a major trade route between India and China, but is also credited for facilitating the spread of Buddhism from India to East Asia. During the 19th century, China's growing opium trade with the East India Company triggered the First and Second Opium Wars. During World War II, India and China both played a crucial role in halting the progress of Imperial
Foreign relations of China threat from both domestic and international sources. Social unrest and serious revolts became more common while the regular army had decayed into an ineffective force. Chinese leaders increasingly feared the impact of Western ideas. After 1724 Christian propaganda was prohibited, and after 1757 international trade was confined to the port of Canton under the strictly limited Canton System. European commercial interests sought to end the trading barriers, but China fended off repeated efforts by Britain to reform the trading system. Increasing sales of Indian opium to China by British traders led to the First Opium War (1839–1842). The superiority of