Washington (also known as Mama) was an African American who lived in London during World War II. He owned a bar called Mama's American Bar on Glasshill Street, where Cody McBride was a regular, as was Sharkey.
In late November of 1940, Mama's Bar was invaded by a swarm of Cybermats ordered by their Cyberman masters to destroy the remains of a damaged Cybermat that Sharkey had in his possession. While many customers were killed, including Sharkey, Mama fought back with a shotgun from behind the counter with the help of Ace. He survived the attack and was later questioned by the police who were investigating the incident. He didn't take a liking to the Seventh Doctor at first glance but he softened up after the Doctor expressed his knowledge in the Negro League of baseball. (PROSE: Illegal Alien)