The Tion Hyperspace War, also known as the Mandalorian Hyperspace War, was a full-blown conflict between the Galactic Protectorate and the Mandalorian League instigated by the spark of the Tion-Corporate Uprising, which saw the Tion Cluster and Corporate Sector revolt against Protectorate oversight.
While the war appeared to go in the Protectorate's favor early on such strategic maneuvers as Operation: Red Manta, the Protectorate war machine fell apart when the underwhelming action on the part of the Mandalorians was an intentional move to draw out and spread the Protectorate forces thin. Under the poor leadership of Grand Protector Ushara Tavlijiis Orrt, Protectorate military might was diminished and eventually withdrew to Core sectors. Coruscant fell soon after, and the Galactic Protectorate was reformed as the Tair Republic.