Zhao Jiong (20 November 939 – 8 May 997), known as Zhao Guangyi from 960 to 977 and Zhao Kuangyi before 960, also known by his temple name Taizong after his death, was the second emperor of the Song dynasty of China. He reigned from 976 to his death in 997. He was a younger brother of his predecessor Emperor Taizu, and the father of his successor Emperor Zhenzong. Why Emperor Taizong succeeded his brother rather than Emperor Taizu's grown sons (Zhao Dezhao and Zhao Defang, who both died in their twenties during his reign) is not entirely understood by later historians. According to official history, his succession was confirmed by Emperor Taizu on their mother Empress Dowager Du's deathbed as a result of her instruction. A popular story dating back from at least the 11th century suggests that Emperor Taizong murdered his brother in the dim candlelight when the sound of an axe was allegedly heard. Whatever the truth, Zhao Guangyi had been prefect of the Song capital Kaifeng since 961 where he gradually consolidated power. He was the only living prince during Emperor Taizu's reign (as Prince of Jin) and placed above all grand councilors in regular audiences. In the first three years of his reign, he intimidated the Qingyuan warlord Chen Hongjin and Wuyue king Qian Chu into submission and easily conquered Northern Han, thus reunifying China Proper for the first time in 72 years. However, subsequent irredentist wars to conquer former Tang dynasty territories from the Liao dynasty in the north and the Early Lê dynasty in the southeast proved disastrous: after the failures in the Battle of Gaoliang River and the Battle of Bạch Đằng, the Sixteen Prefectures and Northern Vietnam (at least in their entirety) would remain beyond Chinese control until the Ming dynasty in the 14th century. Emperor Taizong is remembered as a hardworking and diligent emperor. He paid great attention to the welfare of his people and made the Song Empire more prosperous. He adopted the centralization policies of the Later Zhou, which include increasing agricultural production, broadening the imperial examination system, compiling encyclopaedias, expanding the civil service and further limiting the power of jiedushis. All subsequent emperors of the Northern Song were his descendants, as well as the first emperor of the Southern Song. However, from Emperor Xiaozong onwards, subsequent emperors were descendants of his brother, Emperor Taizu. This largely stemmed