Roma CLII
Roma CLII was one of many alternate timelines where the Roman Empire never fell. In this world, the Terrible Lizards never went extinct and they were used in gladiator matches in Wembley Arena and around the globe. However, a volcanic eruption or other disaster in the Americas had launched burning rocks into the sky and created great tidal waves. Red clouds spewing acid rain blocked out the sun, causing all the crops to die. Millions of people starved to death or died while fighting over precious resources.
When Marcus Americanus Scriptor and Quintus Saxus first arrived on this Earth in Londinium, six months after the disaster, they rescued Regina, who explained what had happened; the few hundreds of people left alive were evacuated to Roma I. (PROSE: Warlords of Utopia)