Alfonso IX was a king of Leon in northern Spain who reigned from 1188 to 1230. He was born in 1171 and was known for his efforts to expand his kingdom and strengthen its power. Alfonso IX played a significant role in the Reconquista, the centuries-long effort to reclaim the Iberian Peninsula from Muslim rule. He was also a patron of the arts and education, contributing to the cultural development of his kingdom. During his reign, Alfonso IX established the first Cortes or parliamentary assembly in Spain, which allowed for greater representation of the nobility and common people. His leadership was marked by conflicts with neighboring kingdoms, including Castile, but he also formed alliances that helped to secure his position.