Parthorum Xenocide

This article is about a battle in the /tg/ Heresy project, a fan re-working of the Warhammer 40k universe.

Parthorum Xenocide
Date	811
Scale	sector-wide
Theatre	Parthorum Sector
Status	Decisive Imperial Victory
Belligerents
Imperium of Mankind	Osroene Empire
Commanders and Leaders
Hektor Cincinnatus	Empress Etuili Sevoold
Strength
3rd Expedition Fleet	armed forces of the Osroene Empire
Losses
Outcome
Parthorum Stream secured for Imperial shipping

The Parthorum Xenocide was the Imperium's name for the first of its three wars for the worlds of the Parthorum Sector. Only one Osroene-authored history of the conflict exists, in the little-read annals of the Pretender Sevtal Sevoold. Sevoold refers to this conflict as the Cataclysm, for the coming of the Imperium heralded the destruction of his people.

Background

The Parthorum Sector is defined by a long, stable current in the Warp beginning about 30 light years north of Terra and tracing a path north-west. This phenomenon, known as the Parthorum Stream covers a region roughly 250 light years long and 50 light years wide at its median point. Warp travel within the Parthorum Stream is relatively predictable and safe, and in the hundred centuries since its reconquest in the Great Scouring, only a handful of ships have been lost while in transit.

Osroene Empire

The Parthorum Xenocide destroyed Osroene centers of learning and killed the great majority of that race's scholars. Human savants only became interested in the history of the lost Empire long after its annihilation and have struggled to piece together its chronology. It is clear, however, that the realm was long-lived and stable, and judging by the anti-Imperial revolts after the war the Osroene must have been accomplished in the art of ruling over a multi-species Empire. Although the Xenos were not as advanced as the young Imperium, they possessed the Warp Drive and had used it successfully in the tranquil conditions of the Parthorum Stream.

The Imperium

Due to the limitations of calculated jumps through the Warp, the first decade of Imperial campaigns following the Unification Wars resulted in a fairly small region centered on Sol. The Emperor's construction of the Astronomican on Terra, the Imperium's Great Crusade opened the way to vast territories beyond by increasing the practical Warp jump distance one hundred fold. This technological marvel ushered in a long period of expansion and led to Imperial conflicts with surrounding Xenos, Xenos-led, and Human realms far from Sol.

The Imperium had known about the Parthorum Sector for months before Hektor Cincinnatus was finally granted permission to launch a campaign of conquest. Although the Primarch was perhaps the third-most powerful of the Imperium's warlords, after the Emperor and Malcador the Sigilite, he had faced considerable opposition to his plans among the Terran adepts of the War Council. Ever confident, Hektor had begun planning while the matter was still in dispute, drawing on the reports of Rogue Traders Militant. Adela Exard's navigational and cultural records were of particular value, so much so that Exard and her Cruiser Black Joke were among the Rogue Trader forces hired on to augment First Legion during the campaign.

Imperial Order of Battle

For the outset of the campaign, Hektor had expanded his 3rd Expedition Fleet with the vessels and flotillas of several Rogue Traders Militant. The precise make-up of the forces under command of these idiosyncratic leaders is in doubt and the limited records available often contradict one another. The order of battle described below is therefore somewhat speculative.

• 3rd Expedition Fleet - Hektor Cincinnatus
  • Naval Task Force - Orion Mucius
  • 1st Phalanx, Chrysaspides - Hephaestion Horatius
  • 2nd Phalanx - Erasmos Sergius
  • 3rd Phalanx - Lysimachos Fabius
  • Various Auxilia formations drawn from the Solar Auxilia and The Carlisian Shock Troops.
• Rogue Trader contingents
  • Flotilla of Lord Captain Megasu Athon
  • Cruiser Black Joke - Captain Adela Exard