The first known representation of Britannia as a female figure sitting on a globe, leaning with one arm on a shield, and grasping a spear in the other hand, is on a Roman coin of Antoninus Pius, who died A.D. 161. The figure reappeared on our copper coin in the reign of Charles II., 1665, and the model was Miss Stewart, afterwards created Duchess of Richmond. The engraver was Philip Roetier, 1665. In 1825 W. Wyon made a new design.
“The King's new medall, where, in little, there is Mrs. Stewart's face, ... and a pretty thing it is, that he should choose her face to represent Britannia by,” —Pepys' Diary (25 Feb.).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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