고조선 is considered the first Korean kingdom, believed to have been established around 2333 BCE by 단군, a legendary figure in Korean history. It was located in the northern part of the Korean Peninsula and parts of Manchuria. The kingdom is known for its advanced culture, including the development of agriculture, metallurgy, and a unique writing system. The society of 고조선 was organized into tribes, and it played a significant role in the formation of Korean identity. The kingdom eventually fell to the 한나라 (Han Dynasty) around 108 BCE, leading to the emergence of other states in the region. Its legacy continues to influence Korean culture and history today.