The house of Este had for their armorial bearing a white eagle on an azure shield. Rinaldo, in Jerusalem Delivered, adopted this device; and Ariosto, in his Orlando Furioso, gives it both to Mandricardo and Rogero, adding that it was borne by Trojan Hector. As the Dukes of Brunswick are a branch of the house of Este, our Queen is a descendant of the same noble family.
D'Este was the surname adopted by the children of the Duke of Sussex and Lady Augusta Murray.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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