Celtic Kings: Rage of War

Source: Wikipedia, "Celtic Kings: Rage of War", available under the CC-BY-SA License.

Celtic Kings takes place in ancient Roman times, during the years that Julius Caesar was the military leader of the Roman Empire. There are three main modes: Adventure, single player (a classic RTS Skirmish mode), and multiplayer. Adventure mode includes a tutorial and the main story. In both campaigns, you control a hero named Larax. In the main story, he loses his wife in a Teutonic raid. In grief, he swears vengeance, and gives his body and soul to the Goddess of War, to enable him to achieve his revenge.
There are two main factions, the Romans, and the Gauls. These two factions are diverse from each other, in terms of gameplay. Their units are different, with the superior Roman technology, while the Gauls depend on their numbers. There is a third, non-playable faction, the Teutons, a nomadic people who live in tents throughout the map. If non-allied units get too close to the tent, the Teutons will engage them in combat. These tents can be captured by killing all the Teutons within proximity of the tent.