 Complete the following phrase:  In 1809 during the War of the Fifth Coalition, Frederick William, Duke of Brunswick-Wolfenbüttel raised a force of volunteers to fight Napoleon Bonaparte, who had conquered the Dukes lands. The Brunswick corps was provided with black uniforms, giving rise to their nickname, the Black Brunswickers. Both hussar cavalry and infantry in the force wore a Totenkopf badge, either in mourning for the dukes father, Charles William Ferdid, Duke of Brunswick-Wolfenbüttel, who had been killed at the 