Nicholas Biddle was a soldier of the 2nd Regiment Colored Infantry.
On April 14, 1865, Nicholas Biddle strikes up a chat with Rufus Carlin, who is under the alias Denzel Washington. Rufus makes up a backstory that he's a freeman from Chicago from a free-born family. From this, Biddle correctly assumes that Rufus is literate and asks him to write notices for him and his fellow soldiers for a newspaper entitled "The Colored Tennessean." Biddle tells Rufus he's looking for his children and wife. Biddle explains the last time he saw his wife, she was being sold by a human trader named Robert Clark in Atlanta.
Rufus asks Biddle what he'll do when he finds his family. Biddle explains he is going to work on a piece of his old master's land that President Abraham Lincoln will make his old master give him. Biddle asks Rufus about his military career, but Rufus does not give satisfactory answers. Biddle discovers Rufus was never really a soldier and angrily forces Rufus to leave.
Later, when Rufus is assigned with stopping George Atzerodt from killing Vice President Andrew Johnson, Biddle notices Rufus and finds it suspicious that he's carrying a gun in the vice president's hotel. Rufus tries to explain to Biddle he's trying to save Vice President Johnson, but Biddle doesn't believe him. Rufus tackles Atzerodt as he shoots, making him miss Johnson. Biddle points Rufus' gun at Atzerodt and Atzerodt is apprehended by law enforcement. Biddle offers Rufus a drink.
Later, Biddle is jaded by the assassination of Abraham Lincoln, believing civil rights will never improve. Rufus gives him words of encouragement, saying that things will not be easy, but things will get better.