Hickory is the former Chief Rabbit of Redstone Warren. He was one of the rabbits who were liberated from Cowslip's warren by the Watership Down rabbits. He and several other rabbits including his mate Marigold, decided to live inside Primrose's old home of Redstone. They lived peaceful lives until elil were attracted to the warren and were hunting for the rabbits living there. During this, General Woundwort and Vervain (under the alias of Wheatstock and Chaff respectively), arrived there and wanted to try and turn Redstone into a warren controlled by force and not reason.
At first, Hickory was taken in by Woundwort's guise and it wasn't until it was too late that he found out the truth. Thanks to a bargain he made with Cowslip, who wanted revenge on his deserters, Woundwort tricked Hickory and the others rabbits at Redstone to stay put while their warren gets demolished by man, but Hazel and the others saved them in time. Hickory was reunited with Marigold, and they all now live with Hazel and the others on Watership Down.