Nat Wallace (alternate mirror universe)

Nat Wallace was a Terran Starfleet officer in the early 25th century. He commands the Terran starship, and is the emperor of the Terran Empire in his universe. 

Rise to becoming Terran Emperor
According to "Agent 47", in the mirror universe of Captain Nat's universe, Nat had eventually risen to the rank of Terran Emperor and had wiped out the Klingon-Cardassian Alliance. He supposedly also created clones of himself to fulfill various tasks, one of which may have been sent to a facility inside of a temporal fracture; possibly resulting in said clone being killed by a Gorn claiming to be head of the Gorn Imperium, presumably from another universe.

He also supposedly commands his universe's, presumably originating from his universe's future, given her being of the same class as her prime counterpart, the USS Enterprise (NCC-1701-J).

Alternate Universes
There are, as of 2410, 3 alternate universe versions of Nat active; including his "regular" counterpart, Nat Wallace (alternate universe), Admiral Nat Wallace from the prime universe accessed via a wormhole in the Sarahara Expanse in the alternate universe, and finally, his prime universe counterpart's mirror counterpart, and possibly also this Nat's equivalent alternate counterpart, Nat Wallace (mirror).