The Qin Dynasty officially became the first unified Chinese Empire in 221 BC, when the young King Ying Zheng, who had inherited the throne from his father at the age of 13, declared himself the First Emperor of China. He would later become known by his posthumous name of Qin Shi Huang.
Prior to the unification, China was divided into numerous states, many of them constantly at war with each other. King Ying Zheng, however, managed to vanquish all the other states, unifying what is now known as Greater China. He ordered the construction of the Great Wall of China, and standardized the writing system, currency and legal system across the country.
The process of unification began several years before Ying Zheng was declared emperor in 221 BC. In 230 BC, Qin Shi Huang’s father, King Zhuangxiang, formed a strategic alliance between the six major states of the time – Qin, Yan, Zhao, Han, Wei, and Chu. This alliance was known as the Hegemonial Alliance and was meant to help bring stability to the region.
King Zhuangxiang died in 247 BC and King Ying Zheng took charge of the Qin state. He set out to conquer the other states, which he did one by one, culminating in victory over the state of Chu in 223 BC. It was shortly after this that Ying Zheng declared himself the First Emperor of China.
The Qin Dynasty brought about many reforms, including military, taxation, and currency systems. They also built irrigation systems and roads connecting different parts of the empire. These measures served to further consolidate their power and created a centralized system of government that remained intact for centuries after the fall of the Qin Dynasty.
Ying Zheng is also known for establishing a common writing script for the whole of China, promoting Confucianism as the official imperial ideology, and overseeing the construction of the Terracotta Army. The Qin Dynasty lasted till 206 BC when the dynasty was overthrown by peasant rebellions.
In conclusion, the Qin Dynasty became the first unified Chinese Empire in 221 BC. This marked a major shift in Chinese history as well as world history, as it was the first large-scale political entity in the world. It made a deep impact on the culture, politics and economy of the region.