I tried to be as concise as possible with the title. I created an Empire version of Altara. That gave me the ability to create henchmen, and those henchmen could use life magic. I would think that if I was empire sided, my henchmen would have death magic choices.
Also, if you create an Empire faction from a Kingdom race, like Men, Mancers, Ironeers, etc, when you create your first city you get the "Kingdom formed" message and screen instead of the empire one, same goes for Kingdom Wraiths.