Washington (Illegal Alien)
From Tardis Wiki, the free Doctor Who reference
Washington (also known as Mama) was an African American who lived in London during World War II. He owned a bar called Mama's Bar at that time, where Cody McBride was a regular, as was Sharkey.
Although he didn't like the Doctor at first glance, he softened up after the Doctor expressed his knowledge in the Negro League of baseball.