So called from sedes (Latin, “a seat”). Their introduction into England is by Hume (vol. iv. 505) erroneously attributed to the Duke of Buckingham, who, it is said, gave great offence by employing men as beasts of burden. Sir S. Duncombe used one in 1634, when Buckingham was a boy, and we find it spoken of as far back as 1581. It was introduced into France (in 1617) by the Marquis de Montbrun, and called chaise à porteus.
It is generally said that these chairs were first made at Sedan, on the Meuse; but this is not at all probable, as, without doubt, the invention was introduced into France from England.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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