I thought it was worth putting up some info for those wanting to run Anonymous Classicist games. It is a bit tricky, and may risk giving someone an advantage over others, so I think these guidelines may help.
The easiest solution is simply to use the Anonymous Countries class of game. Then you get the fun of not knowing who is playing which country, but you do all know who all the players are.
If you really want to play a game where noone knows anyone else in the game, the challenge is you have to password protect to ensure it is limited to Classicists, but how do you get people the password? There are really only two ways to achieve this. The first, which is pretty much guaranteed, is to ask someone not playing to be the focal point for password requests. Then the identity of anyone PMing for a password is not known by anyone in the game. But if you want to play in the game yourself (or you think you might want to, for example if it is having trouble filling) then the method tried before is to only post the password here in the Classicists forum. The risk here is of course the Classicists forum is not protected, so anyone could get to see it, but in practice it appears this rarely happens.
If the group is closely managed, there MAY be another way, but I am not sure you manage yourselves so it might not be practical. If the group leader is maintaing a list of Classicists, then you could just PM that list of Classicists with the password (in otehr words, send it to all). The issue with that of course is people may not want to get a PM promoting a game - they may to see those things in a more passsive way by seeing them in the forum.
I hope this helps.