The 63rd Expeditionary Fleet was one of the Imperium of Man's interstellar military expeditions sent out as part of the Emperor of Mankind's Great Crusade to reunite all the human-settled worlds of the Milky Way Galaxy under his rule during the late 30th and early 31st Millenniums. The 63rd Expedition was commanded by the Primarch and Warmaster Horus of the Luna Wolves (later renamed the Sons of Horus) Space Marine Legion.
It formed the core of the Traitor forces that would challenge the Emperor for control of the Imperium during the terrible interstellar civil war known as the Horus Heresy. The 63rd Expeditionary Fleet's attached Imperial Army contingent included the Byzant Janizars, commanded by Lord Commander Hektor Varvarus. The 63rd Expedition was also assisted by the powerful Legio Mortis Titan Legion as well as Horus' massive flagship, the Gloriana-class Battleship Vengeful Spirit. The fleet was known to also contain at least 10 Light Cruisers and 5 mass conveyances for the Legio Mortis Titans.
- Horus Rising (Novel) by Dan Abnett
- Galaxy In Flames (Novel) by Ben Counter
- False Gods (Novel) by Graham McNeill
- Fulgrim (Novel) by Graham McNeill