Rodrigo (or Ruy) Díaz de Vivar (Vivar (Burgos) c. 1044–Valencia, 10 July 1099), known as El Cid Campeador, was a Castilian nobleman, then military and political leader who conquered and governed the city of Valencia. Rodrigo Díaz was educated in the royal court of Castile and became the alférez, or chief general, of Alfonso VI, fighting against the Moors in the early Reconquista. Later exiled by the king, El Cid left service in Castile and worked as a mercenary for other rulers, both Muslim and Christian.
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