Paulus Atreides aka The Old Duke Atreides (d. 10154 AG head of House Atreides, was the nineteenth Atreides Duke of Caladan, father to Leto Atreides I, grandfather to Paul Atreides (Duke of Arrakis and Emperor of the Known Universe), and great-grandfather to Leto Atreides II (the God-Emperor). The Old Duke ruled Caladan as a siridar fief bequeathed by the Corrino Padishah Emperor, most likely Elrood IX. He was a bullfighter until losing his life to a bull.