She was born in year 10, 191 after the foundation of the Spacing Guild on planet Arrakis to Jessica Atreides. Her father Leto Atreides had died eight months earlier. She was a younger sister to Paul Atreides and through their mother a granddaughter to Vladimir Harkonnen.
Her native planet was also known as Dune. The name accurately describes it as a desert planet. The planet was notable for its production of the spice Melange, a highly addictive drug used to expand consciousness and lifespan.
Alia was apparently born with the powers of prophecy and second sight. She was raised in a community of Fremen led by her brother in an effort to control the planet and its production of Melange. During the original novel, her powers are only hinted at. But she personally poisons her grandfather while in support of her brother.
The character was further explored in Dune Messiah through her relationship with Hayt. At the finale of this second novel, Paul departs into the desert to die. Alia is named Regent and is given the obligation to raise her nephews including heir Leto Atreides II.
In Children of Dune, Alia becomes progressively more witch-like and less human. Falling under the possession and influence of the spirit of her deceased grandfather, the Baron Vladimir Hakonnen, Alia abuses her powers as Regent and becomes a ruthless tyrant. Her nephew, Leto Atreides, returns from exile and subjects her to the Trial of Possesion.