Olive Green on the walls gives a dining room that settled, dug-in feeling, like a long dinner that nobody wants to leave. It is green without being loud, more like dried herbs and old wood than anything bright. Under warm light it reads cozy and a little moody, which is exactly what you want around a table at night.
To keep it from going too dark, run Warm Tan on the trim and around the windows. It is a soft, sandy neutral that lifts the room and lets the olive breathe. Then bring in Walnut Brown as your accent, on a sideboard, the chairs, or a frame or two, to ground everything and tie the wood tones together. Olive on the walls, tan on the trim, walnut on the furniture, and the whole room feels warm and pulled together.