I'd like to put forth Blood and Magic as an RGD suggestion. An old RTS game released by Interplay in 1996. Unfortunately it was released around the time that Warcraft and Command and Conquer were overshadowing everything.
For some reason the full version I have doesn't have the intro cinematic, but the demo does. Supposedly you could find the intro in the demo and move it into the full version folder, but these days it's just easier to watch it on Youtube.