Wudi is the posthumous name of Emperor Wu of Han, who was the seventh emperor of the Han dynasty of China; he ruled from 141–87 BC. His reign lasted over half a century and is one of the longest in Chinese history. A famed military campaigner, Wudi led his armies on great expeditions that resulted in the vast expansion of territories under his rule. The autocratic emperor, through his relentless campaigning, brought southern China and northern and central Vietnam under his control and established dominance over the Korean kingdom of Wiman Joseon, which had slipped out of Chinese influence. Even though he significantly expanded his empire through aggressive military campaigns, these wars depleted much of the empire’s reserves and wealth. He declared new taxes and implemented business policies to increase state income, which made him unpopular among his subjects. While his reign was marked by prosperity in its early years, the final years were filled with financial difficulties and political unrest. Wudi also introduced various religious and cultural changes into society. He promoted Confucianism as the ideological foundation of governance and was obsessed with finding the path to immortality.