In the next year I will begin research on a new project that is historical fiction (not alternative history/fantasy) set in 47 - 71 CE. Most readers, I assume, will be familiar with the Latinized versions of places, names, etc. However, I will not be writing from the POV of the Romans. Any thoughts on using original names versus Latinized versions of names?
Give me an example. BTW E& D is published, on Amazon along with a short story. Buy/download a copy, give me a review
I don't think you need to use Latinised versions. Anyone who knows who Boudicea is pretty likely to work out who the fiery Iceni chief's wife Boudikkia is. Even if they don't, will it matter? In his Arthur books, Bernard Cornwell used the Roman names for towns, like Isca and Eboracum. I didn't recognise all of them, but it didn't stop me enjoying the story.
I used period names in the Eagle and the Dragon, like Eudaemon Arabia for Aden. But for every chapter where people were on the move, the chapter began with a little map showing the route, starting point and destination, and any places enroute. So for example when they were going from Myos Hormos, past Berenice and Ptolemais on the Hunt to Eudaemon Arabia, they could see they were going from the northern fork of the Red Sea with stops at ports along the west coast, ending up at Aden at the mouth of the Red Sea.
I think you'd be fine with either, just keep it consistent. If you're writing from the Celtic or Germanic or whatever POV, it's going to be more jarring for your target audience to see them all using latinized names anyway. In alternate history stories (which I know yours isn't), readers often have to decipher what cities are being described in ways not used in the real timelines, and I think there's a lot of readership crossover. Sudden thought, you could make it clear which way your going early on by having a minor character use a Roman word for something or someone, and have one of your principals excoriate him for doing so.