Lorn V was the 5th planet in the Lorn system and the setting of Warhammer 40,000: Dawn of War: Winter Assault.
It was held by the Imperium of Man for a long time until the arrival of Chaos Space Marines, and then the Orks. For many years there was a bloody war on the snowy planet, between the Orks and the Chaos forces under Lord Crull. It was a one sided fight, for the Orks were too divided to pose any threat. It was under Warlord Gorgutz the Orks became a menace, and the war became increasingly tougher. General Sturnn, having learned that the remains of a Titan were still on Lorn V, launched a invasion on the planet, to reclaim both the planet and the Titan. The Eldar under Farseer Taldeer also secretly invaded the planet, to stop the Necrons who were stirring beneath it.
When the Imperial Guard came, Lord Crull and Warlord Gorgutz struk a uneasy Alliance and worked together to obtain the Titan.
It is unknown what actually transpired on the planet, or it's faith after the war. Farseer Taldeer was able to stop the Necrons, but lost one of her own Farseers to the Orks and many of her warriors against the Forces of disorder. General Sturnn was killed by Gorgutz and his head was put on his 'pointy stikk' along with Lord Crull. It is unknown what happened to the Titan or the Imperial Guardsmen.