Caladan

Caladan is a fictional planet in the Dune universe created by Frank Herbert, first mentioned in the 1965 novel Dune.

Overview
Caladan, the third planet of Delta Pavonis, is the ancestral fiefdom of House Atreides, who have ruled it for twenty-six generations, from the ancient Castle Caladan. An ocean planet, Caladan's surface is predominantly covered with water; its climate is characterized by much precipitation and strong winds, but is tolerable enough to make special and expensive weather control measures unnecessary. Habitable land is often characterized by soft meadows, swamps, and dense forests. The resource base of Caladan consists mainly of agriculture and biomass, with fishing and the locally grown pundi rice serving as the primary sources of sustenance for its people. Other traditional products include wine, whale fur, corals, certain gemstones, and livestock, most prominently thorses and cattle.

Original series
In Dune (1965), Duke Leto Atreides leaves Caladan for the desert planet Arrakis to assume temporary control over the melange-mining operations there. Leto's son Paul Atreides ultimately rises to lead the entire native Fremen population of Arrakis, using his subsequent control of the planet and its supply of the valuable spice melange to depose the Padishah Emperor of the Known Universe, Shaddam Corrino IV.

In 1969's Dune Messiah, Paul rules the universe from Arrakis, and it is noted that Jessica has been granted control of Caladan. After Paul's death, Jessica returns to Arrakis in Children of Dune (1976) to assess the state of Paul's empire, which is being ruled by Leto and Jessica's daughter Alia until Paul's twin children come of age.

Five thousand years later during the events of Heretics of Dune (1984), the planet is simply known as Dan.

Legends of Dune
The Legends of Dune prequel trilogy (2002–2004) by Brian Herbert and Kevin J. Anderson, set over 10,000 years before the events of Dune, chronicles the struggle between humans and thinking machines that would eventually become known as the Butlerian Jihad. In the series, Vorian Atreides, a human trustee of the machines who turns against them, spends time on Caladan and falls in love with a local woman named Leronica Tergiet. Though Vorian continues traveling the universe even after the fall of the machines, his heirs establish the Atreides dynasty there.