He was instrumental in settling the differences between the various branches of the Imperial House, the House of Alman, House of al-Qair and House of Rautha: In 603 AG he persuaded Harmon II al-Qair to step down in favor of Audrii I, the proper heir of Shaddam I, who restored the House of Alman to the throne.
Iason managed to concentrate most of the imperial power in his hands and reorganized the government reestablishing the principles of the Great Convention; now instead of a chaotic personal rule now it became a trierarchy: The Imperial seat, the Landsraad and CHOAM and the Spacing Guild. He arranged regular meetings for the Landsraad.
The Imperial power was diluted and the Emperor became responsible for his actions to the Imperial Family, themselves controlled and balanced by the Imperial Household, its offshoots the Imperial Cousines and the Sardaukar Over-Bashars.
For his contributions, in 635 AG Iason was named Count Aramanli by the Emperor, and married Princess Salusa his daughter, thus becoming a member of the Imperial Household. His sons were Count Heraklios II Atreides and Demetrios VIII Atreides.