The Eternal City is a world at ninety degrees to our own. It is a world where alchemy works and where the human animus (the spirit of life) can be captured and maintained indefinitely and then put to work in any one of thousands of useful mechanical inventions.
It is a world that lives in the dark shadow of unshakeable moral certitudes that maintain an unfair and oppressive system of class and social division.
It is also a world of progress and ambition, greed and heroism, sinister conspiracies and astounding selflessness. Where a few good people can peel back the darkness, even if only briefly.
In our timeline it would be 1898. In the world of Eternal City it is also 1898 but there the similarities end.
The creation of this world was made possible in 1745 by the discovery of the Animus and the victory of Alchemy over rational science. Reason was dead and the need for a monarchy went with it.
Machinations runs using the Dead Simple RPG core rules.