It starts around 10,000 BC and goes through the centuries up to the present (and future), becoming increasingly complex as societies form and whatnot. Participants currently join as either indigenous peoples created by themselves, join as part of indigenous peoples created by existing players, or join as foreign explorers/colonizers/etc. It starts around 10,000 BC. Centuries pass, tribal societies undergo changes, Europeans start to arrive, presumably colonies will form, eventually independent states will come about and the modern world will be reached. Gameplay starts off simple but becomes increasingly more involved as the turns go by.
Link is here http://eregime.org/index.php?act=idx (it's called "Artan" and the whole game at this point is played via private forum areas, so anyone not playing can't actually see what's going on in game at the moment)
Someone on there mentioned vDiplo and said some players here may be interested, which is why I made this thread.
The admins of the forum the game is held on (eRegime) are also willing to promote vDiplo.