Ensemble Studios

Landmark sequel to Age of Empires. Rome has declined, and Western civilization has fallen into an era of social and cultural deterioration. You must guide an ancient medieval clan, and build it into an empire of kings, castles, and knights.

Groundbreaking RTS from Ensemble Studios. Set over thousands of years, from the dawn of human civilization to the height of the Roman Empire, you guide a stone age tribe from a hunter-gatherer culture to a mighty empire.

Age of Mythology is an RTS set within the major historical mythologies - Greek, Roman, Egyptian. It is in the same play style as Age of Empires II, and with good reason. AOM is from the same developer, and same "series" as AOE2.
From Ensemble Studios, the creators of Age of Empires and Age of Kings, comes Age of Mythology, a game that transports players to a time when heroes did battle with monsters of legend and the gods intervened in the affairs of mortal men.

Age of Empires III is the latest entry in the empire-building RTS series from Ensemble and Microsoft. The game is set in colonial America, and covers its colonization and eventual independence, from 1500AD to 1850AD.