El Cid ( he of the great beard ) a Castillian knight was born Rodrigo Diaz de Vivar in 1043 and spent most of his life fighting the Muslims.
Cid comes from the Arabic " sidi " meaning lord.
His most important achievement was when he defeated the Almoravids and took the city of Valencia from the Muslims in 1093-4.
He died in 1099.
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