Alfonso II of Castile was a medieval king who ruled from 1166 to 1187. He was part of the House of Jiménez and is known for his efforts to expand the territory of Castile during the Reconquista, a period when Christian kingdoms sought to reclaim land from Muslim rule in the Iberian Peninsula. His reign was marked by military campaigns and alliances that strengthened his kingdom. Alfonso II was also notable for his support of the Catholic Church and the establishment of various monasteries. His reign contributed to the cultural and political development of Castile, laying the groundwork for future kings and the eventual unification of Spain.