In an alternate timeline in which Khan Noonien Singh won the Eugenics Wars, the Prometheus was a Khanate Earthfleet starship in service during the late 24th century. It was under the command of Princeps Ethan Locken. The ship's holographic counsel Khan Noonien Singh was projected as an elder statesman.
By 2376, the Defiance was assigned to the region near the Cardassian Control Zone in the Bajor sector and reported to Lord-Commander Sisko on Station D9. Quadrant Command compared Defiance's lacklustre results with the victories of Prometheus. (ST - Myriad Universes novella: Seeds of Dissent)