Answer
Alfonso VI had no direct family relation to El Cid, the renowned Castilian knight and warlord. El Cid, born Rodrigo Díaz de Vivar, served as a loyal vassal and military leader under Alfonso VI, King of León and Castile, during the 11th century. Their relationship was built on political and military alliances, with El Cid's exceptional military prowess and strategic acumen proving invaluable to Alfonso VI's reign and territorial ambitions.