and, by a pun, M. Sedantaire (Mr. Sedentary)
Nicname for Napoleon III. [He] was so called, because he surrendered his sword to William, King of Prussia, after the battle of Sedan (September 2, 1870).
(E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898)
Napoleon III was the subject of a number of nicknames, including, “Badinguet”, “Boustrapa”, “Man of December, “Man of Sedan”, “Man of Silence”, “Rantipole”, and “Verhuel”.