Corrin is a planet that orbits the red giant star Sigma Draconis.
In the original Dune novels Corrin is mentioned in passing, primarily because of the imfamous Battle of Corrin that was fought in the star system. It was during this battle that House Corrino emerged as the ruling house of the Imperium.
In the 'Legends of Dune' prequel novels Corrin is described as a radiation-prone world (due to the red giant status of its star) that is barely habitable to humans. Corrin was the location of Omnius Prime after the destruction of Earth. As a result of the Great Purge Omnius was confined to the planet for several decades, before being destroyed by the armies of the League of Nobles.