Who is Bellingham from Chains and what is their importance?

Bellingham is a member of the Patriot Army and Curzon's owner. He promises Curzon that he will help free Isabel if she spies for the Patriots. He also promises to free Curzon if he enlists in the army during wartime in his stead. Bellingham breaks both of his promises, and as a result, Isabel and Curzon are forced to remain in slavery despite their sacrifices.