So called from monteros d'Espinoza (mountaineers), who once formed the interior guard of the palace of the Spanish king. The way they came to be appointed is thus accounted for:- Sanchica, wife of Don Sancho Garcia, Count of Castile, entered into a plot to poison her husband, but one of the mountaineers of Espinoza revealed the plot and saved the count's life. Ever after the sovereigns of Castile recruited their body-guards from men of this estate.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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