Naming Historical Figures

I'm tempted to keep it simple. If the difference of name is not fundamental to the story then use the one that is most common at the time of the story...
Which version of the name will be most used/familiar in the story?
If you character is claiming heritage then they will probably want to associate themselves with the older name...
Is having them called "Wyntrikaide, heir of Hventrikaide" feasible?

 

Rule with names:

Keep them short. Or failing that, memorable. Otherwise, the names tend to get glossed over in the readers mind. Once in a while you can get away with introducing a character with the proverbial 'mile long name,' but that's usually a minor figure. If a regular, use the short version.

Long dead heroes are among the exceptions to this. But even their names can be shortened, or they can be referred to via a title or some such.

 

I'd go with their original name from where they came from. It adds flavor and context to the story be educating the reader about another aspect of the world you've created (i.e., explain something about where the character came from).
Changing their name to fit the language in the place they've gone would be like giving Aristotle a new name today - rather than using his historical Greek name - because no one (or almost no one, anyway) names their children Aristotle today.

 

I think you can do a bit of both. There's an excellent passage in one of the Malazan books where a group of 'Teblor' youths stumble upon a trapped creature. They recognise it as a 'Forkassil.' The true name of the creature is 'Forkrul Assail,' which the youths are somewhat aggressively reminded of after they rouse the creature in question. She also informs them that the true name of their own people is 'Toblakai.'

So, names can change over years, and when passed from language to language. Ye Olde English is a fine example of that. I think you can play around with it, for sure, but I'd say that the link needs to be obvious, and use it sparingly or it gets annoying.