Gratian Caerellius was an Imperial colonial and archeaologist that worked under the East Empire Company during the third era. Gratian was present during the construction of Raven Rock and served his part in the town's growth.
Gratian Caerellius was serving the East Empire Company as a miner for the Raven Rock Mine, which primarily excavates Ebony Ore from the ground. He had helped build the Imperial-Charter township, making it what it is today. With the establishment of Raven Rock, the town was in need of guards and Caerellius decided to join the first regiment of the Raven Rock Guard. Eventually, Gratian returned back to Cyrodiil with his wife and son to explore the ruins of Tamriel under the watch of the East Empire Company. Gratian's exploits throughout Tamriel is left largely unknown, at some point, he garnered an assistance named Millius who documented his findings along with Gratian. Gratian had left Raven Rock before it had become a territory of the Great House Redoran.
During Gratian Caerellius' travels after Raven Rock, he was married and had a child named Rellicus Caerellius, both of whom would travel with Gratian around the world. On the 30th of Rain's Hand in 4E 10, Gratian was given an assignment from the East Empire Company in Raven Rock about their sudden discovery of the Bloodskal Barrow in the Ebony Mines. A month later in Second Seed, Gratian and his group had arrived onto the docks of Raven Rock, which is now under the occupation of the Great House Redoran, much to his surprise. Gratian and Millius had recovered the Caerellius House by it would constantly be covered in Ash. His family would take residence in the Redoran household. On the 9th of Second Seed, the two archaeologists had traversed the Bloodskal Barrow where Gratian learned about the Bloodskal Clan and discover the Bloodskal Blade.
Tempted by the Blade's mystery, Gratian had pulled the Bloodskal Blade from its pedestal, much to the dismay of Millius. The moment he had picked up the blade, a group of Draugr had attacked the two. Millius had fought valiantly but had succumbed the power of the Undead Nords. Gratian was able to fend off the remain Draugr but was mortally wounded in the process. With the Bloodskal Blade in his hands, Gratian died in peace, accepting his fate, hoping that whoever found his journal, would show it to his superiors and to tell his wife that he loves her. He died on the Second Seed of 4E 10.
Unbeknownst to them, Gratian had died in his journey to Bloodskal Barrow. His wife and son were forced to stay on the Island of Solstheim and work in the land, being the only Imperials on the island. Rellicus Caerellius had become a miner in another section of the Raven Rock Mine until he was killed by the local Reavers; it is likely his mother died of natural causes or the frequent ash storms. Rellicus had a son, who would then have a son of his own named, Crescius Caerellius, who would become the foreman of the Raven Rock Mine. The East Empire Company gave a false story about Gratian's death, saying he died of a rockfall. In 4E 181, the Ebony Mines of Raven Rock were exhausted and closed down by Lleril Morvayn, the leader of the town. Crescius had strongly believed that there was still Ebony deep within the mines and had stayed in Raven Rock, becoming one of the last Imperials to live in the town.
In 4E 201, Crescius discovered letters between Gratian and the East Empire Company, realizing that there was more to the Raven Rock Mine than meets the eye. Crescius made several attempts to explore the mine but was stopped by his wife, Aphia Velothi. And so, he tasked an estranged warrior to explore the ruins, to find the remains of Gratian and his discovery. Deep into the mines, the warrior discovered the entrance to Bloodskal Barrow and both Gratian and Millius' remains. The traveler picked up the Bloodskal Blade and entered the ruins, defeating the Dragon Priest, Zahkriisos in the process. With the records needed, the traveler gave it to Crescius, who was able to reopen the mine, ushering in a new era of prosperity to Raven Rock.