Annals of Rome begins in 273 BC with the player in control of the Roman state. Unlike other war-strategy games, the aim is not military victory but survival for the longest time possible. In the initial few hundred years, the player will be at war with Carthago, Greece, Gauls.... If any of these ancient powers are conquered and annexed, they will continue to rebel until the time of historical death for that state (for Macedonia this is 146 BC). They will then be succeeded by a new power which will also try to destroy the Roman state. In this way Carthago will be followed by the Numidians, and the Parthians with Persians ... The player will always face 13 active states/nations under computer control.
Source: Wikipedia, "Annals of rome", available under the CC-BY-SA License.