List of emperors of the Han dynasty

Emperor pottery miniatures of infantry (foreground) and cavalry (background) from a royal tomb bronze handle with traces of red pigment, in the shape of a dragon's head; for Han emperors, the dragon could represent either good or bad omens depending on circumstance. The rulers of the previous Shang () and Zhou (256 BC) dynasties were referred to as 'king' ( ). By the time of the Zhou dynasty, they were also referred to as the Son of Heaven. In 221 BC, King Ying Zheng of Qin completed the conquest of all the Warring States of ancient China. To elevate himself above the Shang and Zhou kings, he accepted the new title of Emperor ( ) and is known to posterity as Qin Shi Huang, the 'First Emperor' of Qin. The new title of emperor was created by combining the titles for the Three Sovereigns and Five Emperors from Chinese mythology. This title was used by each successive ruler of China until the fall of the Qing dynasty in 1911. Posthumous, temple, and era names From the Shang until the Sui dynasty (581–618) dynasty, Chinese rulers (both kings and emperors) were referred to by their posthumous names in records and historical texts. Temple names, first used during the reign of Emperor Jing of Han (), were used exclusively in later records and historical texts when referring to emperors who reigned during the Tang (618–907), Song (960–1279), and Yuan (1271–1368) dynasties. During the Ming (1368–1644) and Qing (1644–1911) dynasties, a single era name was used for each emperor's reign and became the preferred way to refer to Ming and Qing emperors in historical texts. Use of the era name was formally adopted during the reign of Emperor Wu of Han (), yet its origins can be traced back further. The oldest method of recording years—which had existed since the Shang—set the first year of a ruler's reign as year one. When an emperor died, the first year of a new reign period would begin. This system was changed by the 4th century BC when the first year of a new reign period did not begin until the first day of the lunar New Year following a ruler's death. When Duke Huiwen of Qin assumed the title of king in 324 BC, he changed the year count of his reign back to the first year. For his newly adopted calendar established in 163 BC, Emperor Wen of Han () also set the year count of his reign back to the beginning. Since six was considered a lucky number, the emperors Jing and Wu changed the year count of their reigns back to the beginning every six years. Since every six-year period was successively marked as yuannian (), eryuan (), sanyuan (), and so forth, this system was considered too cumbersome by the time it reached the fifth cycle wuyuan sannian () in 114 BC. In that year, a government official suggested that the Han court retrospectively rename every "beginning" with new characters; Emperor Wu accepted this reform in 110 BC. Since Emperor Wu had just performed the religious Feng Shan sacrifice at Mount Taishan, he named the new era yuanfeng (). This event is regarded as the formal establishment of era names in Chinese history. Emperor Wu changed the era name once more when he established the 'Great Beginning' ( Taichu) calendar in 104 BC. From this point until the end of Western Han, the court established a new era name every four years of an emperor's reign. By the Eastern Han, there was no set interval for establishing new era names, which were often introduced for political reasons and celebrating auspicious events. == Regents and empress dowagers ==