posthumous name (shi) of the eighth emperor (reigned 74–49/48 BC) of the Han dynasty (206 BC–AD 220), who ascended the throne when the designated heir apparent behaved indecorously during mourning ceremonies for his father. The Xuandi emperor strove to abate the harshness and widespread corruption that had marked the preceding two reigns. Under him the Han dynasty probably attained its greatest prosperity. Even the Xiongnu tribes on the northwest frontiers, who had been warring with China for more than two centuries, were persuaded to cease their raids during his reign. He was succeeded by his son, Liu Shi, who reigned as the Yuandi emperor.