I could recommend you the following: for historical
Crazy girl shin bia - it's a manhwa
Dear my girls - manhwa
Kiss to my prince - still manhwa
backstage prince- even tho it's not so historical...
Godchild - Count Cain - there are actually two series of Godchild but the one with Ludwig (I think that's the main characters name) I haven't read. - it's more of a mistery than a historical manga, but this is how I've seen it characterised..
Kamikaze kaitou Jeanne - has mistery too..
Mademoiselle butterfly
and some mystery:
Barajou no kiss
Doubt and Judge - as a mistery fan, those are a must!
Dolls and [Switch] - with the brackets you're more likely to find the narcotic story and not the shojo manga..
D.N.Angel - anime only
Death Note- if, by chance, you haven't read it
Darker than black
Jisatsu Circle - suicide groups
Spiral: suiri no kizuna and Spiral-alive
Uzumaki - more of a horror story .. along with Gyo
Vampire Knight... well it has it's mistery points... week but they are
biggrin I think I'm missing some .. but if those are not enough... pm or wait for me to come by again!
xd