The Kingdom of Qin was one of the seven major states during the Warring States period in ancient China. It was located in the northwest region and became known for its strong military and effective governance. The kingdom's strategic location allowed it to expand its territory and influence over neighboring states. In 221 BC, the Kingdom of Qin unified China under the leadership of Qin Shi Huang, the first emperor. This marked the beginning of the Qin Dynasty, which implemented significant reforms, including standardized weights, measures, and writing systems. The dynasty's achievements laid the foundation for a unified Chinese state.