The Imperial House Corrino was once the deadliest and grandest House Major found within the Known universe, and for many thousands of years the imperial family of the Imperium. The official residence of the Imperial House Corrino was the planet Kaitain while their personal fief was the ancestral exile planet Salusa Secundus.
Over the subsequent millennia, the Imperial House Corrino maintained a firm grip on the Empire.
House Corrino's rule was defined as absolute while one of its members sat on the Golden Lion Throne. Moreover, House Corrino maintained a large vote in the Landsraad Council, larger than any other Great House.
During their Imperial rule, House Corrino maintained arguably the most powerful army in the known universe - the Sardaukar. Through their superior abilities the Corrinos were capable of crushing any military opposition. It was said that the only way the Corrino Sardaukar could be defeated would be through the combined forces of all the Great Houses of the Landsraad.
The Corrino were, presumably, just rulers of the Imperium as no known issues other than Arrakis were known, but they would backstab and use treacherous tactics in order to maintain their seat in power but without getting openly involved, such as when they supplied Sardaukar to the Harkonnen to deal with the Atreides.
Downfall of the Corrino Empire
Complacency, inactivity and corruption eventually weakened the Sardaukar. That, combined with ill-considered decisions by Shaddam Corrino IV and the scheming of the Bene Gesserit, eventually saw other Great Houses, particularly House Atreides, acquire significant respect and credibility in the Imperium.
In an attempt to discredit House Atreides and retain their hegemony, the Imperial House Corrino under the leadership of Shaddam IV, devised a plan to dispose of their potential rival by ordering them to take over the planetary fief of Arrakis, and then disposing of them through their hated rival House Harkonnen, via an audacious, and highly illegal, invasion of the planet.
Initially the plan looked to have succeeded. Duke Leto Atreides I was killed, and his family abandoned in the deep desert. However, a gradual uprising by the native Fremen, led by the mysterious Muad'Dib caught both House Corrino and House Harkonnen off-guard.
After the Arrakis Revolt and the Battle of Arrakeen, House Corrino was forced to relinquish the Golden Lion Throne, after thousands of years of rule, to the Atreides. The Corrinos witnessed the legitimization of Atreides rule through Paul Atreides' marriage to Shaddam's eldest daughter Princess Irulan Corrino. Shaddam IV and the remainder of his family were then sent into effective exile on the harsh planet Salusa Secundus, where one of Shaddam's four other daughters, Wensicia Corrino plotted the Great House's re-emergence.
However, Wensicia's plans were also foiled by the Atreides, and her son, Prince Farad'n Corrino became the official concubine of his step-cousin, the Crown Princess Ghanima Atreides. In addition to providing the Atreides offspring that were needed for Leto II's Golden Path, Farad'n also acted as his official scribe. House Corrino had lost most of it's power with the ascension of Paul Atreides to the throne but the House continued to exist at least through the end of Leto II's reign.