The State of Wei was one of the seven major states during the Warring States period in ancient China, which lasted from the 5th century to 221 BCE. It was located in the northern part of present-day Henan and Shanxi provinces. The state was known for its strategic military tactics and played a significant role in the political landscape of the time. Founded by the Wei clan, the state reached its peak during the 4th century BCE under the leadership of notable figures like Sima Qian. However, it eventually fell to the stronger states, particularly Qin, which unified China in 221 BCE, marking the end of the Warring States period.