At this period in military history there are styles repeated throughout European armies so it is rather difficult to ascertain the officer’s origins. There isn’t sufficient detail in the uniform to identify a unit; though cleaning and further research may prove fruitful. France established a number of hussar regiments from 1692 onward, recruiting originally from Hungary and Germany, then subsequently from German-speaking frontier regions within France itself. With most European Hussar and Cavalry uniforms of this period being very similar it is difficult to be 100% sure of the origin of the picture, so there is a possibility he is British or even Prussian, but the sitter seems most likely to be French in our opinion.
A Hussar was a member of any one of several types of light cavalry used during the 18th and 19th centuries, beginning in Central Europe. The French hussar of the Napoleonic period was armed with a brass-hilted sabre, a carbine and sometimes with a brace of pistols, although these were often unavailable. A famous military commander in Bonaparte’s army who began his military career as a hussar was Marshal Ney, who, after being employed as a clerk in an iron works, joined the 5th Hussars in 1787. Indeed, this picture has some similarities with a portrait of the very same Michel Ney as a Sous-Lieutenant in the 4th Hussars in 1792, by Adolphe Brune in Room 1792, Versailles Palace, Ile-De-France, France.
Pictures of Hussars from this period are not easily found so this picture is scarce, whilst also being a very decorative and strong portrait evoking a distinctive period in military history.