Kaidan was a male Cardassian and a Gul in the Cardassian military.
In 2371, during political instability that occurred after Kag Duzek's death, Gul Kaidan claimed to be acting on behalf of the Imperial Council when he demanded that the crew of Deep Space 9 turn over a vessel that had travelled through the Bajoran wormhole. This brought him into conflict with Dukat, who also wanted the vessel. (DS9 novel: Valhalla)