Who is Clouter from Sharpe's Trafalgar: Richard Sharpe and the Battle of Trafalgar, October 21, 1805 and what is their importance?

Clouter, former slave, swam out to Chase's ship and became a seaman. He is described as a large man, who fought valiantly during battle. Wounded several times, Clouter lost several fingers and still managed to help get Lord William's body out of the hold after Lady Grace shoots him.