Herleven

"In many ways the planet Herleven is symbolic of the Primarch of the Astartes that call it Home, Sanguinius. It is flawless in its beauty, but underneath it is very, very, dangerous."

- Inquisitor Dorlomin The Planet Herleven is a Deathworld located on the boarder of segmentums Pacificus and Obscurus and is the Homeworld of the Angels of Rebirth Astartes Chapter. It has been a key defense for the Pacificus Segmentum against the Eye of Terror since it was rediscovered in 358.M34. Originally colonized in 350.M33 it was cut off from the rest of the Imperium for a millennium by a warpstorm that encompassed the entire system.

Discovery and Settling
In M33 Imperial Astronomers discovered a potentially habitable in the Halikos sector and a small exploritor fleet was sent to investigate. Only a fifth of the fleet returned telling tales of a planet of extraordinary beauty with a moon rich in resources. Unfortunately they weren't the only ones interested. The fleet had run into a Force of Chaos that seemed to be investigating the planet themselves and had battled the exploritor fleet. The Imperial Forces had driven them off initially but lost many forces themselves and had sent a portion of their fleet back for repairs and call for aid.

In response the Lord commander organized a Imperial Fleet to help hold the system, including the Blood Angels 4th company and Raven Guard 6th companies. When they arrived they found that a powerful force of Iron Warriors had arrived and had already destroyed a full half of the exploritor fleet, with more traitor forces arriving while a unforseen warpstorm eveloped the system

While the warp storm enveloped the System the Imperial forces battled the arriving Traitor forces. After a three day battle in space over the primary planet, Herleven, the Loyalist forces had lost half the Mechanicus fleet and were in dire need of aid. Finding themselves trapped in the system and without outer communications, the Blood Angels Captain Elias and the Raven Guard Shadow Captain Arthas worked out a desperate plan in an attempt to destroy the Iron Warriors flagship, Crusher of Hope. The Blood Angels Battle Barge, Bloodmoon, alongside two imperial Navy Strike Cruisers, and three Frigates, would signal the Iron Warriors and challenge them to battle. Meanwhile the Raven Guard's Strike Cruisers would go into orbit around the planet's moon, Patmos, and shut down as many systems as possible in order to stealthily flank the Iron Warriors. The plan succeeded but at great cost. The Bloodmoon was destroyed before the Raven Guard could join the fray and near the end of the battle, most of the Raven Guard force was lost when the central Strike Cruiser suffered a dire malfunction during a critical moment when it attempted to fire it's Jovian pattern Nova Cannon, which failed catastrophically, causing the vessel to suffer a cascade failure as the ship's warp engines exploded spectacularly, destroying two of the three cruisers.

With the system won but a majority of their forces lost, unable to escape the warpstorm, the remaining Imperial Forces had one option remaining to them; settle the planet or die. Originally the remaining Mechanicus forces wanted to turn Herleven into a new Forgeworld, but given the necessity for food production to sustain the Imperial Forces after their stores inevitably ran out the planet was given to the Imperial Navy forces as well as the remaining Astartes. The Mechanicus would claim the more resource rich Petros as their forgeworld.