Buddhism is believed to have spread to China via the Silk Road. When the Silk Road opened in the 2nd century BC, missionaries and pilgrims spread Buddhism to China. Chang Ch'ien was recorded to have first introduced Buddhism to China when he heard about India and Buddhist beliefs upon his return to China. Around the 1st century BC, a Buddhist community is said to have lived in China. But the best-known story of the spread of Buddhism is when the Han emperor Mingdi dreamed of Buddha in 68 CE and sent Cai Yin, his official, to find out more. Meanwhile, Mingdi learned from his ministers that he had seen Buddha, "the God of the West" in his dream. After 3 years, Cai Yin returned to China with Buddhist teachings and two Buddhist monks who taught Buddhism throughout China. Soon a Buddhist community formed and continued to grow with the introduction of Buddhist books, art, and temples. Buddhism spread in China and throughout China because at the time Buddhism was introduced to China, China was suffering from the period of disunity. The Chinese needed something to unify and bring them together. Buddhism arrived at exactly the right time and its teachings appealed to the Chinese. By 514, near the end of the period of disunity, there were 2 million Buddhist monks in China teaching Buddhism, which helped unify China after anarchy. Many books were translated into Chinese, temples were erected, and the emperor proclaimed Buddhism as China's main religion. Magnificent temples were built where Buddhism was taught and worshiped and Buddhism in China reached its peak during the Sui and Tang dynasties. The Grand Canal in China is 1,800 kilometers or 1,115 miles long, the longest man-made canal in the world...... middle of paper ... the emperor had a stroke and soon died, leaving the Empress Wu and her four sons. Empress Wu appointed her fourth weakest son as emperor so that she could rule through him. However, in 690 CE he stepped down from the throne and Empress Wu became the only ruler to kill anyone who got in her way. Although she was cruel and ruthless, she was a good ruler, appointing people based on their intelligence and tests, not on their wealth or social status. While in power, Empress Wu also increased agricultural productivity and reduced taxes so that peasants could keep a greater share of their harvests. In 705 CE, Empress Wu's third son overthrew her, and Empress Wu died soon after. Many people believe that she was a cruel woman who only wanted power, but others believe that she had the strength and character of a female leader. She was not well liked, but she nonetheless deserved respect for making China strong and rich..