Xavier Harkonnen [223 BG - 164 BG] was a prominent and highly respected military commander leading up to, and during, the Butlerian Jihad. He later murdered the Grand Patriarch Iblis Ginjo: an action that tainted his family's name for many centuries.
Life
Xavier was born to wealthy and prominent aristocrats within the League of Nobles, Ulf Harkonnen and Katarina Harkonnen. At the age of six, Xavier's parents were killed in an assault by thinking machines, and he was later adopted by Emil Tantor and Lucille Tantor.
Seen as an upcoming commander, Xavier received a military commission at the age of 19. Soon afterward, he distinguished himself in the Battle of Zimia by taking control of the shell-shocked Salusan Militia and commanding them to a famous victory over the forces of Omnius, specifically a group of cymeks led by Agamemnon. During this battle his lungs were permanently damaged and subsequently replaced by Tleilaxu-supplied organs.
Following the battle, Xavier courted Serena Butler, daughter of Viceroy Manion Butler Senior. It was by Xavier that Serena conceived the martyr, Manion the Innocent, who she bore as a slave of the robot Erasmus on Earth.
After Serena's disappearance from the League of Nobles, Xavier married her sister Octa Butler. Through this union, Xavier became the patron of both the Butler and the Harkonnen families. The couple bore three daughters together, the youngest of whom went on the be the genesis of House Corrino.
During the Battle of Earth, Xavier was credited with the contentious idea of bombarding Earth with atomics, an action that not only desroyed the then Omnius Prime, but also obliterated all life on the planet.
During the Butlerian Jihad Xavier became a Primero in the Army of the Jihad alongside Primero Vorian Atreides, and the two became firm friends, in part because of their contrasting styles of leadership and strategy. Xavier commanded in many victorious such as the Battle of IV Anbus and the Liberation of Ix.
After Serena Butler's death, Xavier accompanied Grand Patriarch Ginjo in an embassy to invite Tlulax to the League of Nobles. During his stay, he was contacted by a former Tercero of the battle of IV Anbus, Hondu Cregh, who was a captive organ repository for the Tlulaxa. Cregh revealed the truth about the organ farms that supplied the League with replacement organs. During the revelation, he was noticed by Ginjo who explained his motives to the Primero. Xavier realized that he would not reach Salusa Secundus alive.
Death and Legacy
Xavier explained his plans to Quinto Paolo who accompanied him. Xavier had no other choice, and after Paolo left the return ship on a spacefolder Kindjal with a message to Primero Vorian Atreides, Xavier blocked the transport ship and headed it towards the Thalim star, killing thus himself as well as freeing humanity from the evil Patriarch.
However due to subsequent machinations of his political allies and his widow Camie Boro, the truth of that event was distorted: Iblis was eventually revered as a martyr and Xavier was marked as a traitor. As a result, the Harkonnen name became tarnished and Xavier's descendants adopted the surname Butler. Xavier's grandson, Abulurd, later ressurected the name after learning an alternate account from Vorian Atreides, much to the dismay of both his family and the League in general.
In an ironic twist, each and every Padishah Emperor ever to rule humanity has been a straight line-descendant of Xavier Harkonnen, the man who is seen as one of history's great traitors.