Interview over at STGUCory Nelson: The first is the Federation which starts between movies 1 & 2. You’re playing as Mathew Renolds and taking over your first command along the Klingon Neutral Zone. I don’t want to get too far into what the storyline does, but you’ll be doing some heavy interaction with the Klingons and a little with the Romulans. The Klingon Campaign picks up about 30 years after the Federation one ends, right around the Khitomer Massacre, putting you at war with the Romulans. There, you’ll be taking the Captain’s chair as Commander Kadir, a Klingon of a noble house, who is eager to work his way up the Klingon ranks and prove his warrior status. There’s a bit of an uneasy truce with the Federation at this stage so you’ll not only be protecting your borders against the Romulans, but also you’ll be trying to figure out how to interact peacefully with the Federation. Klingons haven’t had a lot of practice at that. As you progress in each campaign, your crew can gain promotions which will increase their abilities.
There was a screenshot floating around showing a TNG-era Vor'cha-class attack cruiser that raised a few eyebrows; guess that explains that.