Have you ever read a great historical novel, gotten really into it, devoured it all the way to the end...and then realized there was no historical note? Nothing to tell you about what was fact and what the writer invented for the sake of the story, nothing about her research process or the sources she used.
Historical fiction is just that, fiction, but most readers pick up a book because they have at least a superficial interest in the time period. They want that time brought to life. And when they've finished, many of them would like to know a little about the nonfiction behind the fiction.
I don't understand authors who don't include at least a teeny historical note. Sometimes all you really need is a page: this is what's real, this is what I made up, the end. Maybe mention a book or two that you found especially helpful.
I'm a fan of going above and beyond that. I love books where the author has taken several pages at the beginning and end to explain the history behind the fiction, and which sources were important. Stephanie Dray and Laurel Corona are good examples of this. I especially liked the glossary/pronunciation guide at the end of Corona's Penelope's Daughter.
My all-time favorite novel (so far) for its end material is Pharaoh's Daughter by Julius Lester. Throughout the book, a retelling of Moses' childhood, Lester takes great care to be as authentically ancient Egyptian as possible, even calling Egypt "Khemet," the Egyptians' own word for their nation. At the end he includes a glossary, an extensive bibliography (two whole pages, small type) and a lengthy but fascinating author's note that describes the evolution of the novel as well as his journey to Judaism.
I also fall more toward that end of the spectrum when it comes to author's notes. I probably wouldn't go so far as to use almost all of the terms that my characters would actually have used. I'm fine with calling Egypt, Egypt, although kudos to those of you who are committed to absolute accuracy. But I have literally dozens of academic articles saved on my computer and scores of books on my shelves, and it would be a real shame not to acknowledge the hard work of all those scholars who helped make my story possible. I'll likely provide a basic bibliography at the end of my novel. Then I can go ape-wild with a super-detailed bibliography on my website or blog.
On the other hand, I'm the kind of person who doesn't consider herself truly knowledgeable about a civilization until she's fluent in their (probably dead) language. So you should take anything I say with a grain of Dead Sea salt.