At the top of my head I can only think of two period shows as amazing as Mad Men, which are The Knick and Downton Abbey. Hope that helps :)

I'm affraid I've already went through all of DA - but The Knick is news to me, I'll give it a try! ^ ^

Have you tried Breaking Bad? It's nothing like Mad Men except it has great characters with tragicomedy storytelling.

There's also a not-so-good Amazon series called Good Girls Revolt which is in the same style as Mad Men.

House of Lies isn't set in that period at all, but it is, kinda sorta along the same vein, a team of consultants trying to get rich making their clients richer. Based on true memoirs, it's edgy, slick, fun...although, admittedly, not quite as well polished from end to end as Mad Men; be that as it may, I enjoyed the entire run and, when it was over, I'd have watched more.

Of course, House of Cards is at a whole other level. I find it breathtaking in scope, subtleties, nuance, character exploration...

And then, for a real change of pace, there's Orange Is the New Black. Criticisms notwithstanding, I have enjoyed (most of) the characters, their stories, how they survive, etc.

You'll be hard pressed to find something that comes close to Mad Men, especially the first 3 seasons... It had a mood and atmosphere that set it apart from other TV shows, although it did become more TV as the series progressed and the finale was almost cheesy...

If you don't mind a bit of violence, then Broadwalk Empire is good for the first 2 seasons and looks like what I'd imagine it's time period was like, but it doesn't have the feeling Man Men has... Still better than most TV in terms of style and entertainment. It trails off quickly after the second season though...

Anybody watched any Billions? I haven't yet, but I like Paul Giamatti (his turn as King John in Ironclad was intense). Billions looks like some slick TV.