Kanzian was an admiral in the Barrayaran Imperial Service. He was a space operations specialist and considered by his peers to be a better strategist than the Regent of Barrayar, Aral Vorkosigan, who suggested him as a possible Regency candidate.
He was trapped in the capital during Vidal Vordarian's attempted coup against Vorkosigan, but was rescued by Commander Simon Illyan. Kanzian then joined Vorkosigan's forces and spoke to wavering Admiral Knollys on his behalf. He was present at the staff conference when Cordelia Vorkosigan presented the head of Vidal Vordarian to her husband.