Emperor Qin Shi Huang was the first emperor of a unified China, ruling from 221 to 210 BCE. He is known for centralizing power and implementing significant reforms, including standardizing weights, measures, and even the writing system across his empire. His reign marked the beginning of the Qin Dynasty. One of his most famous projects was the construction of the Great Wall of China, aimed at protecting the empire from invasions. He also ordered the creation of the Terracotta Army, a vast collection of clay soldiers buried with him to accompany him in the afterlife.