The Monteros de Espinosa are the oldest Bodyguard unit of Royal Guards in Europe. Founded by the Counts of Castile around the year 1006 and kept in service by the Castilian Sovereigns and posterior Dynasties that inherited their Kingdoms and united with. It is still part of the Spanish Guardia Real. It was a privilege reserved only for the local Hidalgos of the oldest mountainous districts of the County of Castile at the time of its foundation, who could ask for or be asked by the Crown for its service at any time.