After defeating his main rival in the Chu–Han struggle, Liu Bang declared himself emperor (Emperor Gaozu). This created a new imperial government that replaced the short-lived Qin order and set the basic framework for Han rule.
In 200 BCE, Emperor Gaozu was checked by the Xiongnu at the Battle of Baideng. Afterward, the Han court relied heavily on heqin—marriage alliances and tribute-like exchanges—to reduce frontier pressure while the dynasty consolidated at home.
After Gaozu’s death, Empress Lü became the dominant political figure as empress dowager and regent. Her regency stabilized succession in the short term but intensified court factionalism and suspicion within the imperial Liu clan.
In 180 BCE, Emperor Wen took the throne after turmoil following Empress Lü’s death. His reign is remembered for lighter taxes and a cautious style of rule that rebuilt trust in government and strengthened the dynasty’s finances.
In 154 BCE, several regional kings rebelled against Emperor Jing’s efforts to reduce their autonomy. The rebellion was crushed within months, and the court then tightened control over the semi-independent kingdoms, strengthening central government.
In 138 BCE, Emperor Wu sent envoy Zhang Qian toward Central Asia to seek allies and information. Although the mission faced setbacks, it expanded Han knowledge of the “Western Regions” and is widely linked to the early formation of Silk Road connections.
In 9 CE, court official Wang Mang took the throne and founded the Xin dynasty, interrupting Western Han rule. He introduced sweeping reforms that aimed to reshape landholding and currency, but his regime faced widespread opposition and crisis.
In June–July 23 CE, rebels defeated Xin forces at the Battle of Kunyang. The battle became a decisive turning point that undermined Wang Mang’s authority and helped bring the Xin dynasty to collapse later that year.
In 25 CE, Liu Xiu (Emperor Guangwu) re-established Han imperial rule after the Xin interregnum. The dynasty’s center of power shifted east to Luoyang, and the restored state is known as Eastern (Later) Han.
In 105 CE, court official Cai Lun is traditionally credited with presenting an improved papermaking process to the Han court. Cheaper, more practical writing materials supported administration, education, and record-keeping across the empire.
In 184 CE, a large-scale religious and peasant revolt erupted across parts of the empire. Although the Han state and regional armies suppressed the main rising, the conflict weakened central authority and increased the power of warlords and court factions.
In 189 CE, warlord Dong Zhuo took control of the capital and deposed Emperor Shao, replacing him with Emperor Xian. This openly demonstrated that armed strongmen could dominate the imperial court, accelerating the breakup of effective Han rule.
In the winter of 208–209 CE, Cao Cao’s forces were defeated by a southern coalition led by Sun Quan and Liu Bei at the Battle of Red Cliffs. The outcome prevented Cao Cao from controlling the south and helped set the stage for long-term regional division.
In late 220 CE, Emperor Xian abdicated to Cao Pi, ending nearly four centuries of Han imperial rule. This transfer formalized the shift from a unified dynasty to competing successor states, commonly known as the Three Kingdoms era.
Han Dynasty (202 BCE–220 CE)