Gideon Claybourne is the father of Deacon Claybourne and the late Beverly O'Connor. Through his son's relationship with the late Rayna Jaymes he is also the paternal grandfather of Maddie Conrad and the paternal step-grandfather of Daphne Conrad.
He is first mentioned during Season Two while Deacon and Beverly are arguing and again during one of Deacon's AA meetings. He is a recovering alcoholic who was abusive to his family and this is where Deacon picked up his own fondness for drink.
He makes his first on-screen appearance in the final season episode The House That Built Me when he shows up at a performance Deacon gives for a radio show. Deacon refuses to talk to him but later visits him at his motel, only for the visit to descend into an argument with Deacon telling his father that he never wants to see him again. A series of flashbacks show Gideon arguing with Deacon's mother and berating his son for playing his music before Deacon points a shotgun at his father telling him to leave the family alone.
After Maddie talks to Gideon, telling him that she, Daphne and Scarlett are all that he has left, she gets Deacon to have a civil conversation with his father which results in Gideon being taken home to stay with him and the girls.