Eeth Koth was a Zabrak male from the planet of Iridonia, that was discovered to be Force-sensitive and was brought to the Jedi Temple to be trained as a Jedi.
Koth soon became a Jedi Master and was appointed to the Jedi High Council He participated in various conflicts during the Clone Wars.
Koth fell in love with the female Zabrak Mira.
On 19 BBY, Koth was forced to step down from the Jedi High Council and left the Jedi Order. The former Jedi Master put himself on exile at the same time Supreme Chancellor Sheev Palpatine, the public persona of Darth Sidious, destroyed the Jedi Order by issuing the execution of Order 66, forcing the clone troopers to kill the Jedi.
As Palpatine established the Galactic Empire of which he became its Emperor, Koth remained in Exile and severed his loyalty to the Jedi. He eventually fell in love with Mira, a female Zabrak, and by 14 BBY the two lovers were married, Mira later expected the birth of Koth's child. Koth also became a priest in the Church of the Ganthic Enlightenment, officiating weddings and funerals.
The family was found by Darth Vader.
Mira eventually gave birth to her daughter with Eeth Koth present, the child was also force-sensitive like her father. Mere minutes after the child's birth, however, Darth Vader and three Inquisitors arrived to confront Koth.
The former Jedi initially tried to plead with Vader to allow him and his family to remain in peace while Mira told the nurse droid to give her the baby. When Koth's attempt to bargain with Vader didn't work, he engaged in a lightsaber duel with him while his wife escaped with their daughter.
Mira was chased by the Inquisitors while she tried to arrive at her father's hovercraft with her daughter. She nearly made it but was caught up by the Inquisitor Thirteenth Sister, who used the child's Force-sensitivity to find her. Desperate, Mira pleaded to the Inquisitor woman to woman to let her go with her child, which seemed to work as Akaris let her go into the hovercraft.
After the death of Eeth Koth, his daughter was given to the nursemaids.
As the craft departed, however, Akaris used the Force to rip the child from Mira's arms as the craft was mid-flight. Mira broke down and begged her father to go back, but he refused as they could both die if they went back.
As the duel between Koth and Vader continued, the former Jedi Master soon realized that the Inquisitor had captured his daughter, which distracted him and allowed Vader to impale the Zabrak through the back, killing him. The Inquisitors gave Koth's daughter to Vader who used the Force to silence her after she didn't stop crying. The baby was soon given by Vader to two nursemaids to be put into Project Harvester.
Eeth Koth's family first appeared through Eeth Koth in the 1999 film Star Wars: Episode I The Phantom Menace, the first installment of the Star Wars prequel trilogy. However, Koth's family wasn't shown to have been formed until the 2018 comic book issue Darth Vader 19. By contrast, the Star Wars Legends continuity had Eeth Koth growing up as an orphan in Nar Shaddaa's violent slums, having no one when the Jedi Order came for him.