The Piast princes were the first ruling dynasty of Poland, emerging in the 10th century. They played a crucial role in the formation of the Polish state, with Mieszko I being the most notable figure, as he united various tribes and accepted Christianity in 966, which helped to strengthen the nation. The dynasty continued with notable rulers like Bolesław I the Brave, who expanded Poland's territory and influence. The Piast dynasty lasted until the 14th century, when it was succeeded by the Jagiellonian dynasty, marking a significant transition in Polish history.