The Ingenium was a machine operated by a powerful sorcerer named Vuhon. After the events of The Elder Scrolls IV: Oblivion and Vivec's disappearance, the Ministry of Truth became unstable and the people of Vivec City feared the total destruction it would cause if it were to fall. Vuhon and Ezhmaar Sul made a deal with Daedric Prince Clavicus Vile, which resulted in creation of the Ingenium to keep the Ministry of Truth floating. In order to work properly, the Ingenium needed mortal souls. Firstly, only the souls of criminals and outlaws were used to run the Ingenium. The Ingenium consumed around ten souls per day. Eventually, Vuhon found out that appropriate souls could power the Ingenium for months.
The Ingenium was operated for five years since Vivec's disappearance during the Oblivion Crisis. Ezhmaar Sul's wife, Ilzheven, was chosen to be one of the sacrificed because she had the right sort of soul. Sul tried to rescue her, but the following fight between him and Vuhon damaged the Ingenium, and without anything to keep it in the sky, the Ministry of Truth crashed into Vivec City. It is widely believed that this is the direct cause of the events of Red Year. Ezhmaar Sul and Vuhon were banished to The Fields of Regret, Clavicus Vile's Realm of Oblivion, where Vuhon made another deal with Umbra to create a second Ingenium. With the help of the second Ingenium, Vuhon and Umbra managed to rip a portion of land from Oblivion and float towards Tamriel.
The Ingenium was destroyed when prince Attrebus plunged Umbra into the Ingenium. In order to avoid Umbriel falling into the Imperial City, Mere-Glim guided the floating city to the Realm of the Hist.