Basically for the last two months I've gone back and forth between researching and working out plots/characters in my head until last week when I began writing. Writing a contemporary story involves some research but historicals like this one a lot more (even when I think I know an era and area pretty well). When I write a story based in the past, I do not regard them as historical novels. An historical novel must stay exactly with what happened as best as can be determined. A romance, set in an historical period, has more latitude and should not be taken as a history book by those looking for such.
What I like to do is figure out general language, but I don't put the character's dialogue into cant or some kind of historical jargon that today's reader is scratching their head figuring out. I don't favor reading such books unless they were written back then. I definitely don't want to write them. I do though like to have a good idea of what the food would be like, how the people lived, the political climate, colloquial expressions, and roughly what was going on in their world before I set my fictional characters into it.
Although I knew a lot about Tucson, there was more I needed to know especially since this book would be more set in the town with more political aspects because my hero, a deputy United States Marshal, was in more of a political position.
For research, I found several good books on Tucson's history, lots of information online, as well as one book on United States Marshals of early Arizona and New Mexico. The one thing you learn fast, when you research history, is there is often as much fiction as fact in any history. You pick and choose what you want/need from the mix.
When I spent time in the Arizona Historical Museum in Tucson, I took some great photos of old photos (asked permission first). This story will follow one set two years earlier. The first one was easier because it happened mostly in the out of beyond as well as Tombstone with Tucson only the beginning and ending. I researched but didn't have to know as much.
By the end of 1885, terms were being worked out for the surrender of Geronimo for what would be the last time. The outlaws still ran rampant in the back country, Tucson was a small town but growing fast thanks to the railroad coming in 1880 which was the beginning of a big change for the Old Pueblo. The mix of cultures, the ethnic difficulties, the tenor of the times all made for an interesting setting and very enjoyable research.
Once you know the world in which they will live, that's when you can set your characters which is where I am now with my writing.
All photos from Arizona Historical Museum