Casimir III The Great was the King of Poland from 1333 to 1370. He is known for his significant contributions to the development of the Polish state, including legal reforms and the establishment of a strong central government. His reign marked a period of prosperity and stability in Poland. Casimir III also expanded the territory of Poland through successful military campaigns and strategic marriages. He was the last ruler of the Piast dynasty, and after his death, the throne passed to the Lukomorye dynasty through his daughter, ensuring a continuation of his legacy in Polish history.