Alternate Rome

An alternate Rome existed at many times, either created in alternate timelines or as natural parallel universes.

Known Worlds
During the War in Heaven, there were many Known Worlds where the Roman Empire never fell. Designated as "Romas", these were collected into the Empire of Empires. (PROSE: Warlords of Utopia)

The Rani's Rome
The Roman Empire of an alternate 10 BC was created for in a pocket dimension, maintained by the entity known as Iam. In this alternate timeline, Rome generated electricity, built airships and steam-driven galleys, broadcast radio, and had many other disturbing anachronisms, due to them gaining access to the databanks of the Doctor's TARDIS when Iam created a copy of the ship's control console. The Rani also tried to manipulate the alternate Cleopatra VII's three children, but failed. Realising that this pocket dimension was too small to maintain its growing population, the Doctor was able to teach Iam how to create a new world, allowing Iam to transfer the population of this world to a new Earth, which came to be known as Terra Nova. (PROSE: State of Change)

Magog's Rome
In another alternate Rome, Magog and four other Malevilus were worshipped for having led Rome in conquest of the galaxy. They later provided the alternate Romans with the technology to invade other dimensions. The Fourth Doctor imprisoned Magog in an empty dimension and started a revolution that led to the destruction of the other four Malevilus with the help of the robot Vesuvius. He left this Galactic Roman Empire in the hands of Vesuvius. (COMIC: Doctor Who and the Iron Legion)

20th century Rome
Investigating why the multiverse was contracting, the Sixth Doctor became stuck on several worlds. One was a 20th century Earth where the Roman Empire never fell. This alternate universe diverged from the prime universe when Julia Caesar became empress of the Roman Empire and had her life prolonged by an alien technology. The Roman Empire eventually owned sixty percent of Earth. (PROSE: Spiral Scratch)