Iason Atreides was son of Count Pausanias III Atreides.
He was instrumental in settling the differences between the various branches of the Imperial House: In 603 AG he persuaded Harmon II al-Qair to step daown in favor of Audrii I, the proper heir of Shaddam I.
In 635 AG Iason was named Count Aramanli and married Princess Salusa, the daughter of Audrii I, becoming a member of the Imperial Household.
His son was Count Heraklios II Atreides.
Contributions
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.
The Imperial power was diluted and the Emperor became responsible for his actions to the Imperial Family, controlled and balanced by the Imperial Household, its offshoots the Imperial Cousines and the Sardaukar Over-Bashars.