I've been flicking through the 3.5 version of Ravenloft: The Masque of Red Death. This setting detailed Gothic Earth, a world much like the 1890s of our world with added weirdness due to an entity known as the Red Death. Players tended to play 1890s characters such as aristocrats, Holmesian detectives or the like. You could be excused for thinking it is a Cthulhu clone, but there is more emphasis on D&D supernatural elements rather than the alien science-fiction explanation of H.P. Lovecraft's universe.
Sadly the mechanics the original Red Death used belonged to AD&D 2nd Edition - a rather odd system that did not have any skills system and was relatively cumbersome. A D20 conversion was cobbled together for the RPGA Living Death campaign - which I would think on the surface would be a better system as it actually has a skills system.
Shockingly the RPGA conversion was carried over into the professional Masque books. The class system therefore a bit rubbish. While some classes are almost 1:1 retreads of their D&D 3.5 counterparts (for example a Soldier is pretty much a D&D fighter, a criminal is a D&D rogue in the old thievery sense). On the other hand some classes are a bit crap - for example a parson (i.e. priest of a real world faith). While you would expect the parson to be equivalent to a cleric, the parson gets no spells, and at 8th level can turn undead as a mystic of 4 levels lower.
Obviously it would be a bit odd if every rabbi/priest/whatever goes around casting cure light wounds. Which makes one wonder why you don't play a mystic, but whatever...
Also don't get me started on the dandy (d4 hit points, some skills, same starting money as a tradesman, physician or performer). This poor guy gets some vague influence power and nothing after level 2 except some bonuses to a new skill called Appraise).
I've a vague idea to run Masque of Red Death mixed with an Innsmouth/Broughty Ferry setting (seriously some of the inhabitants you see during working hours in the real Arbroath look like Deep Ones). But I'd rewrite a lot of the classes to be worth taking.