Emperor Zhenzong of Song (23 December 968 – 23 March 1022), personal name Zhao Heng, was the third emperor of the Song dynasty of China. He reigned from 997 to his death in 1022. His personal name was originally Zhao Dechang, but was changed to Zhao Yuanxiu in 983, Zhao Yuankan in 986, and finally Zhao Heng in 995. He was the third son of his predecessor, Emperor Taizong, and was succeeded by his sixth son, Emperor Renzong at the end of his reign. From 1020 he was seriously ill, but retained power despite this. Because of his illness, day-to-day rule of China was often placed in the hands of his third wife, Empress Liu. Emperor Zhenzong's reign was noted for the consolidation of power and the strengthening of the Song Empire. The empire prospered, and its military might was further reinforced. However, it would also mark the beginning of a foreign policy towards the Khitan-led Liao dynasty in the north that would ultimately result in humiliation. In 1004, the Khitans waged war against the Song Empire. Emperor Zhenzong, leading his army, struck back at the Khitans. Despite initial successes, in 1005, Emperor Zhenzong concluded the Chanyuan Treaty. The treaty resulted in over a century of peace, but at the price of the Song Empire agreeing to an inferior position to the Liao Empire, and also agreeing to pay an annual tribute of 100,000 ounces of silver and over 200,000 bolts of silk. The admission of inferiority would come to plague the foreign affairs of the Song Empire, while the payments slowly depleted the empire's coffers. He was responsible for ordering the shipment of 30,000 bushels of quick-maturing rice seed from the Fujian Province to the lower Yangtze basin in 1011–1012, improving agriculture. Emperor Zhenzong stressed the importance of Taoism at his imperial court. It was during his reign that the so-called Heavenly Texts, which glorified the Zhao family, were allegedly discovered. This was followed up by imperial sacrificial ceremonies carried out at Mount Tai.