221 BC

In 221 BC, China saw a significant turning point when Qin Shi Huang declared himself the first emperor, unifying various warring states into one centralized empire. This milestone marked the end of centuries of fragmented states and laid the foundations for imperial China. He implemented major reforms, standardized weights, writing, and currency, and began building the early layers of what would become the Great Wall. The year represents a pivotal moment in Chinese history, highlighting the consolidation of power and the beginning of a long-lasting imperial era.