Duke Leto Atreides

Jessica is Leto’s longtime partner and ducal concubine, and they share a son. Their affection persists despite Leto’s deliberate public coldness, which sustains an appearance of distrust for political security.

Leto is Paul’s father and heir-designated; he trains Paul in leadership and expects him to uphold the Atreides position. Their shared concern for the people is evident during the rescue of the spice workers.

Leto is Alia’s father; she is still unborn when Jessica undergoes the Water of Life rite.

The Old Duke is Leto’s father. His legacy and harsh influence shaped Leto’s colder, more demanding side, and his portrait is an important family emblem.

Halleck serves Leto as a trusted officer, guard, and adviser. Leto values his sharp observation and diplomatic instincts, and Halleck responds with loyalty and familiarity.

Kynes serves as the Imperial Planetologist on Arrakis and is drawn into the Atreides’ affairs, recognizing their political significance and ordering Fremen to protect Paul.

As a sietch leader, Stilgar negotiates with Leto over Fremen customs and a political bond, establishing the possibility of cooperation.

Hawat is Leto’s Mentat and Master of Assassins, responsible for intelligence and security. Leto relies on his assessments, though he sometimes proceeds against Hawat’s warnings.

Leto leads House Atreides and its people, carrying the responsibility of their move to Arrakis and the danger posed by the Harkonnens.

Yueh is Leto’s Suk doctor, but he betrays the Atreides under coercion involving his wife. He leaves Leto a poison tooth and a message explaining that Leto did not die alone.

Idaho is an Atreides fighter and trusted household retainer. Leto assigns him to guard and surveil Jessica, reflecting both his confidence in Idaho and the danger surrounding the family.

Leto hopes to establish peace and prosperity on Arrakis, where the Fremen are a powerful local people whose support could affect the Atreides’ survival.

Mohiam considers Leto's endangered line within the Bene Gesserit breeding program and tells Jessica that she expects him to lose Arrakis.

Tuek is a powerful smuggler whom Jessica invites to the Atreides dinner to signal cooperation against graft and provide a possible escape route. His presence is politically useful but makes Leto wary.

Nefud is among the Baron’s guards after Leto’s death and helps clear the poison-gas scene. The passage does not establish a direct personal bond between them.

Bewt is a powerful water magnate whose allegiance is under contract to the new Duke. He challenges Leto’s customs and policies while retaining economic leverage through water.

Mapes serves as the Atreides household’s Fremen housekeeper. She is mortally wounded during the attack and attempts to warn Leto.

Kynes is the Imperial planetologist and Judge of the Change, while Leto is the incoming ruler. They begin with mutual suspicion, but Leto’s concern for workers earns Kynes’s reluctant respect and liking.

The Baron calls Leto his cousin while holding him captive and interrogating him. The Harkonnen assault has destroyed Leto’s House, and Leto dies using poison against the Baron and his men.

Rabban serves the Harkonnen campaign against the Atreides, helping impose the Baron’s violent rule on Arrakis.

The Emperor turns against Leto because the Duke’s trained forces threaten the balance of imperial power, ultimately enabling the destruction of House Atreides.