The enmity between Wolverine and Sabretooth is one of the most personal and bloody feuds in the Marvel Universe. For over a century, Sabretooth, AKA Victor Creed, has waged a series of savage mind games and vicious attacks against his former friend. Their conflict was put on hold with the founding of Krakoa and Sabretooth's imprisonment in the island nation's Pit.
Source:https://www.cbr.com/wolverine-sabretooth-war-benamin-percy-victor-lavalle-interview/