Leibrock (German), a military tailcoat with long tails, similar to the coatee. The photo shows Prussian staff officers of the Napoleonic Wars wearing the «Leibrock». These 15 mm miniatures by Minifigs have been painted with artist acrylics and they are based for the Empire III wargame.
Source: Meyers Großes Konversations-Lexikon, 6. Auflage 1905–1909