As a historian, he is best known for his 1876 anti-Normanist 2-volume magnum opus Varangians and Rus (Варяги и Русь) which won him the Uvarov Prize of that year.

The composition of the score was divided between César Cui, Modest Mussorgsky, Nikolai Rimsky-Korsakov and Alexander Borodin.

Dissatisfied with his own effort, he passed the text to Alexander Ostrovsky, and the latter used the plot to write the completely new play of the same title.

[1] Gedeonov authored one original play, The Death of Lyapunov (Смерть Ляпунова, 1845) which was produced by Alexandrinsky Theatre and had considerable success, running for 18 performances in its first season.

Later, as the director of the Imperial Theatres, Gedeonov refused to give the permission for it to be produced, describing it as his 'childish fallacy'.