I'm thinking of doing a 1920's New Orleans RP, sort of a contrast of the jazzy, boomy front of the city with the voodo/racist underbelly, and I was wondering how you guys approach period pieces, particularly 20th century ones.

Depends on exactly what I am going to do. A lot of the Rp's I run are based in area's that actually exist and I try to retain a lot of that feeling and era when doing that. Research, using the right street names for the time period, beliefs, customs, etc. Most larger or known cities, it is easy to find actual maps from most time periods. London you can find ones a thousand years old online and updates through out the centuries. The more modern areas, good maps helps a lot.

I also look up dress for the time era and place. Try to keep it looking that way with character creations. Same with how they speak. Looking up turns of phrases. Granted I usually get on a kick for something because I either watched something or read something. So I will use the original inspiration as reference.

With a tampon.

With a tampon.

Dammit Buddha, I was gonna say that XD

So I will use the original inspiration as reference.

Don't think Princess and the Frog works.

With a tampon.

Why did I expect anything better from you?

The most general advice I would give is to look at how books describe their settings and the details that entail that. How they describe not just the look but the feel and the vibe of the location. I find that if you manage to do it, accents can be pretty effective provided they're understandable and don't give off the wrong accent. Also see if you can look up anything about diction as well; find how people of the era would talk and any euphemisms they might use. IE anything from "them" to "colored" to "negros" to whatever else someone might have used to describe a black person.

Drown myself in google links until I have a vague idea of what a character who exists within the setting would act, and how the environment shaped them as opposed to a more modern upbringing. Researching is key.

The first thing I do is decide exactly what I like about a set period and wish to emulate. I then build a framework that the players can easily understand and put their characters in.

I'll use a 1940 art deco RP I did as an example. What draws me to this time frame are the visual aspects. Film noir, detectives, nazis, Italian mafia, etc. Even though it's a time frame I'm familiar with, I did some research to get a better idea for my story. I cintinued to do reaserch any time something came up that I wasn't sure about. Another thing to take into consideration was my player base. These guys were good writers, but bio shock was about as close as they got to anything from the 1940s. So I made an alternate U.S.A. city and basically fused aspects of New York and Chicago together. I did make it a magical setting, but magic could only be used by people who possessed medieval artifacts, and they could only use very specific spells.

It worked out very well. Yes, we had that one guy who didn't understand that remote car starters weren't around in 1940's america. All in all though it worked. We managed to bring the RP to its intended end without strangling each other.

Read and research.

By read, I mean read pieces written contemporaneously of the period in question. Read pieces set in that period, or written by people from that area or that were living in that area at the time. Research everything, but don't worry too much about getting things perfectly. Read lots of non-fiction as well on the themes and period.

Google image and google maps are useful. Do not become super reliant on either on though. Google maps is good for getting a baseline, but New Orleans has had some major changes done to it, so it isn't the same as the modern incarnation.

If you are a quick enough reader, get some books. If that would bog your process down, stick to documentaries.

For New Orleans, off the top of my head, a good place to start might be the the documentary series Jazz by Ken Burns. That particular documentary is legit enough that I once took a class in college that used it as the curriculum. Watch the whole thing. Besides being really good, it's useful to get a large baseline. Even though most of that documentary's first few episodes are pretty much totally in NOLA, knowing the stuff taking place in other parts of the country wouldn't be a bad idea.

That being said, don't get overwhelmed. Research as you go. If you get things wrong, so what. It's an RP; you're not getting graded it on. The research is for depth/achievement/personal development.

You'll probably be surprised though, about how different perception is from historical reality. For instance, it is true that racism was a problem at that period of time, but did you know that one of the biggest sources of racial tension in 1920's New Orleans was surrounding Italians in the French Quarter?