Dukat was the Gul on Terok Nor during the Bajoran occupation. During this time Dukat was known by his men for having relationships with the Bajoran woman who were brought aboard as comfort woman. He fathered at least one child at this time and even had relations with Kira Nerys' mother after she was taken from her family.
Dukat was created for the television show Star Trek: Deep Space Nine.
Dukat's lot in life changed dramatically in the seven years after he lost his command as Gul on Terok Nor. He went back and forth between being at the forefront of the Empire to being a lowly officer on the worst assignments. He even became a rouge commander fighting his own war on a commandeered Klingon fighter. The climax of his career in the Cardassian military ended at a battle on Terok Nor where he saw his daughter murdered right in front of him by his 2nd in command after she confessed she was a Federation spy to her father.
Seeing his daughter murdered right in front of him twisted his mind till he became completely mad. He lost all control and even envisioned people who were not even really there. He also became obsessed with the Bajoran Religion and used it to the best of his advantage. He even created a cult based on the Pa Wraiths that were the evil prophets. Later he even became possessed by one and killed Jadiza Dax who was praying in a temple for the prophets. He was later killed at the fire caves by Benjamin Sisko.