Diagna is a Yokudan, who had a cult of Redguards later devoted to him. He originated in Yokuda during the Twenty Seven Snake Folk Slaughter.[1] Diagna was an avatar of the HoonDing, another Redguard deity, that achieved permanence.[1] He was instrumental in the defeat of the Lefthanded Elves, as he brought orichalc weapons to the Yokudans to win the fight.[1]

In Tamriel, he had a number of followers, who called themselves the Order of Diagna. This order was responsible for defeating the Orcs during the Siege of Orsinium,[1][2][3] and then fading into obscurity, with him now being little more than a local power spirit of the Dragontail Mountains.[1]