Gravius was the Captain of the Salamanders Legion's 5th Company, during the Great Crusade and he took part in the Conquest of One-Five-Four Four with his friend, Captain Heka'tan.

在大远征期间，格拉维乌斯是火蜥蜴军团第五连队的连长，他和他的朋友赫卡'坦连长一起参加了对1544的征服。

As the Horus Heresy unfolded, both Captains would take part in the war against the Traitor Legions on Isstvan V, but when the Dropsite Massacre began, Gravius was one of the few Salamanders to escape. In the Massacre's aftermath, he took command of a Salamanders warship, but it was shot down by the Traitors and crash landed on the fiery world Scoria. The impact caused the warship to be buried beneath Scoria's surface and Gravius and his forces played no further part in the Horus Heresy. They remained forgotten on Scoria for millennia and eventually the Captain's fellow Battle Brothers died, leaving him to keep watch as his body slowly withered away. Gravius was not alone though, as the crew of the warship colonized the area around the crash site and their descendants came to revere the Captain. Eventually though Gravius refused to leave his warship's command chair and in time the door leading to the bridge was sealed. This led Gravius to become a myth to the warship's colony, as one of the Fire Angels that watched over them.

随着荷鲁斯叛乱的展开，两位连长都参加了在伊斯塔万五号对叛徒军团的战争，但当登陆点大屠杀开始时，格拉维乌斯是少数逃脱的火蜥蜴之一。大屠杀发生后，他指挥了一艘火蜥蜴战舰，但它被叛徒击落，坠毁在炽热的熔渣世界。撞击导致战舰被埋在熔渣星的表面下，格拉维乌斯和他的部队在荷鲁斯叛乱中没有进一步的作用。他们在熔渣星上被遗忘了数千年，最终连长的战斗兄弟们去世了，留下他看着他的身体慢慢枯萎。然而，格拉维乌斯并不孤单，因为军舰的船员在坠机现场周围殖民，他们的后代开始尊敬连长。最终，尽管格拉维乌斯拒绝离开军舰的指挥椅，但通往大桥的门还是被封住了。这使得格拉维乌斯成为军舰殖民地的神话，成为守护他们的火焰天使之一。

In M41, Gravius was found alive by fellow Salamanders from the Chapter's 3rd Company, but the Captain was now in a horrifically withered and frail state. By that time Scoria was dying, as its numerous volcanoes would not stop erupting and were quickly tearing the world apart. Though the 3rd Company wished to take Gravius with them, before they left the doomed world, the Captain' power armour had long ago become fused to his command chair. With time running out, the 3rd Company tried to learn of the Legion's history from the Captain, but Gravius's mind had become addled and he remembered little from his vast lifespan. Eventually the Company's Apothecary, Fugis, was ordered to give Gravius the Emperor's Mercy and he then extracted the Captain's Gene-seed. The Company escaped Scoria with the crashed warship's surviving colonists, as well as the power armour of Gravius' fallen Battle Brothers. At the time of his death, Gravius was possibly the oldest living Space Marine in the Galaxy.

在M41，格拉维乌斯被第三连队的火蜥蜴同伴发现还活着，但连长现在处于极度枯萎和虚弱的状态。在那时，熔渣星已经奄奄一息，因为它的众多火山不会停止喷发，并迅速将世界撕裂。尽管第三连队希望带走格拉维乌斯，但在他们离开这个注定要毁灭的世界之前，连长的动力盔甲早已与他的指挥椅融为一体。随着时间的流逝，第三连队试图从连长那里了解军团的历史，但格拉维乌斯的思维已经变得混乱，他对自己漫长的一生几乎没有什么记忆。最终，该连队的药剂师福吉斯被命令给予格拉维乌斯帝皇的仁慈，然后他提取了连长的基因种子。该连队带着坠毁战舰幸存的殖民者以及格拉维乌斯倒下的战斗兄弟的动力盔甲逃离了熔渣星。在他死亡时，格拉维乌斯可能是银河系中现存最古老的星际战士。