The sitter is General Alexandre de Beauharnais (1760-1794), who was the first husband of Josephinee Beauharnais who married Napoleon Bonaparte. General Beauharnais was executed on the guiltoine in 1794.
The portrait is copied from a profile portrait and was probably painted after 1810, when his reputation was somewhat restored as he was the grandfather of the future Napoleon III (1808-1873).
At Beauharnais, Alexandre de (18e s.) there is an engraving (and so the image is reversed) from the same source. For more about him see Alexandre, Vicomte de Beauharnais - Wikipedia, the free encyclopedia 1021