- Damocles Gulf Crusade (742-745.M41) - When the Second Sphere Expansion of the T'au Empire culminated in the T'au crossing the Damocles Gulf and making contact with the frontier worlds of the Imperium in the Timbra Sub-sector of the Lithesh Sector, the Imperium had had enough with the upstart xenos. The T'au were quickly condemned as a potentially dangerous alien species and the Imperium's Ultima Segmentum command launched an Imperial Crusade to expel them from the region. The Scar Lords were one of several Space Marine Chapters that lent their might of arms to the ongoing Imperial campaign. The Scar Lords are known to have taken part in the fighting on the Sept World of Dal'yth. When the Chapter Master of the Scar Lords carved a bloody path through the magnorail tunnels of Dal'yth's government district, Commander Farsight gave permission to the lone XV8 Crisis Battlesuit pilot Sha'ko'vash to intercept. The Monat blasted his way to the heart of the Scar Lords strike force, only to be brought to his knees by the Chapter Master's Terminator armoured Honour Guard. Sha'ko'vash boosted forwards with one last charge, triggering an experimental stasis fail-safe at the exact moment the Scar Lord raised his blade to strike and freezing the two warriors in place at the crux of the conflict. Hundreds of standard years later, the two mighty warriors are still trapped in the resultant sphere of timelessness, raised up outside the rebuilt core assembly house of Dal'yth as a centrepiece monument to the Greater Good.
- War on Vior'los (456.744.M41) - Following the Scar Lords' disastrous boarding action against the T'au flagship Dawn Pioneer, the Scar Lords redirected their efforts to the T'au planet of Vior'los. Failing to conquer it, Chapter Master Caelos sought to destroy the planet by unleashing an Exterminatus, and ordered the drop of a planet-killing warhead on Vior'los. This plan failed when a bold T'au Battlesuit pilot was able to detonate the warhead before it was launched towards the planet.
Notable Scar Lords
- Chapter Master Caelos - Caelos was the last Chapter Master of the Scar Lords and the successor of Chapter Master Durian Raevor.
- Chapter Master Durian Raevor - Former Chapter Master of the Scar Lords, Durian Raevor had been trapped in a stasis field on the T'au Sept of Dal'yth. The stasis field eventually fell and awakened the Chapter Master and the T'au Commander Monat Sha'kanthas. As a result, the two fought in the museum of the city of Gel'bryn. Monat was able to stop and kill Durian with the aid of the renegade T'au Commander Farsight. The remains of the Chapter Master are still present in the museum.
- Epistolary Vaethosis - Vaethosis was the Epistolary and the Pyromancer of the Scar Lords Librarius who served his Chapter for three Terran centuries. He died trying to kill the T'au leadership on Vior'los.
- Captain Shaegrus - Shaegrus was the captain of the Scar Lords 3rd Company.
- Captain Aortura - Aortura was the captain of the Scar Lords 8th Assault Company.
- Ancient Vrendaeon - Vrendaeon was the ancient of Command Squad Caelos.
- Company Champion Treota - Treota was the company champion of the Scar Lords 1st Company.
- Veteran Xaedros - Xaedros was a Veteran Marine of Command Squad Caelos. He served in the Deathwatch.
- Apothecary Darroleon - Darroleon was an apothecary of Command Squad Caelos.
- Techmarine Tarrajaeo - Tarrajaeo was the techmarine of the Scar Lords' Armorium.
- Scabbard of Flesh (Battle-Barge) - The Scabbard of Flesh was abandoned by the Scar Lords after T'au Commander Farsight was able to infiltrate the ship and destroy its Warp-Drive, which led to a daemonic incursion.
The Scar Lords firmly held to the belief that, "The Emperor judges you not by your medals or diplomas, but by your scars."
As such, the members of this Chapter bore their scarred visages proudly.
Often disdaining the use of a helm, many of the Scar Lords left their wounds only partially healed, their facial disfigurements a sign of their devotion to the Golden Throne.
The Scar Lords' Chapter colours are not listed in current Imperial records.
The Scar Lords' Chapter badge is a skull riven by lightning bolts on a terracotta field.
- Farsight Enclaves - A Codex: Tau Empire Supplement (6th Edition) (Digital Edition), pg. 37
- Farsight: Crisis of Faith (Novel) by Phil Kelley, pp. 210, 321, 508, 531
- Redemption on Dal'yth (Short Story) by Phil Kelley
- War of Secrets (Novel) by Phil Kelly, Ch.1