It was a whole coalition of forces that faced off against Napoleon. Soon, new reinforcements will be hitting the Black Powder battlefields to bolster the ranks fighting against the French. They're the Belgians and Dutch and you can see their new sets in this preview.
From the article:
To believe that Albion triumphed over Napoleon with purely British forces would be very wrong: Belgians, Dutchmen and Germans, in various guises, all greatly contributed – and so it will be on Black Powder battlefields, as Dutch and Belgian troops in miniature will be marching onto tabletops soon.