The Kingdom of Lithuania was a historical state that existed from 1253 to 1569. It was established when Mindaugas, the first king, was crowned. The kingdom played a significant role in the region, expanding its territory and influence through various military campaigns and alliances. In 1569, the Union of Lublin united the Kingdom of Lithuania with the Kingdom of Poland, forming the Polish-Lithuanian Commonwealth. This union marked a new era in the region, combining the resources and cultures of both nations, which lasted until the late 18th century when the Commonwealth was partitioned.