Mandalorians
I don't know much of the background behind these people, but I think they may have been patterned after Shaolin monks. He said that the armor and weapons were part of his religion. Clearly Boba Fett didn't come up with that look - the two guys the show's protagonist had to fight in the bar to get his bounty recognized him right away as a Mandalorian.
They seem to never take their helmets off except in private. Even the priestess the show's protagonist went to see in the first episode was wearing one. What she meant about his signet being revealed, or her reference to the Great Purge, are things I suppose we'll learn in time. They appear to be a warrior culture with a lot of customs and rituals. Probably most of them are soldiers, mercenaries, bounty hunters, perhaps law enforcement ... any occupation that could involve combat. I don't think they intend to give us an information dump on the Mandalorians but simply reveal bits and pieces of their beliefs and history organically along with the story.
I like the whole ambiance of the show, they've perfectly captured old school Star Wars. I don't know how much of the creature effects are practical and how much are CGI but they do a good job blending them together. Those paintings they show over the end credits are straight from a classic western. The parallel is clearly intentional. Who knows if they'll be able to keep up the quality beyond what's essentially a two part pilot - but we can hope. I have spoken.