come to be called the Prelude to Dune series. Using some of Frank Herbert's own notes, the duo wrote Dune: House Atreides (1999), Dune: House Harkonnen (2000), and Dune: House Corrino (2001). The series is set in the years immediately prior to the events of Dune. This was followed with a second prequel trilogy called the Legends of Dune, consisting of Dune: The Butlerian Jihad (2002), Dune: The Machine Crusade (2003), and Dune: The Battle of Corrin (2004). These were set during the Butlerian Jihad, an element of backstory that Frank Herbert had previously established as occurring 10,000 years before the events chronicled in Dune. Herbert's brief description of humanity's "crusade against computers, thinking machines, and conscious robots" was expanded by Brian Herbert and Anderson in this series. With an outline for the first book of Prelude to Dune series written and a proposal sent to publishers, Brian Herbert had discovered his father's 30-page outline for a sequel to Chapterhouse Dune, which the elder Herbert had dubbed Dune 7. After publishing their six prequel novels, Brian Herbert and Anderson released Hunters of Dune (2006) and Sandworms of Dune (2007), which complete the original series and wrap up storylines that began with Frank Herbert's Heretics of Dune. The Heroes of Dune series followed, focusing on the time periods between Frank Herbert's original novels. The first book, Paul of Dune, was published in 2008, followed by The Winds of Dune in 2009. The next two installments were to be called The Throne of Dune and Leto of Dune (possibly changing to The Golden Path of Dune), but were postponed due to plans to publish a trilogy about "the formation of the Bene Gesserit, the Mentats, the Suk doctors, the Spacing Guild and the Navigators, as well as the solidifying of the Corrino imperium." Sisterhood of Dune was released in 2012, followed by Mentats of Dune in 2014. In a 2009 interview, Anderson stated that the third and final novel would be titled The Swordmasters of Dune, but by 2014 it had been renamed Navigators of Dune and was published in 2016. In July 2020, Herbert and Anderson announced a new trilogy of prequel novels called The Caladan Trilogy. The first novel in the series, Dune: The Duke of Caladan, was published in October 2020, and the second, Dune: The Lady of Caladan, was released in September 2021. The third novel, Dune: The