Creating characters who feel like living, breathing people is a primary task for any storyteller. We live with them day and night. They wake us up and make demands in the middle of the night. Personally, I miss them like old friends after the story is done. I have to go back and reread my books so that I can visit them.
Here is a fascinating interview with Phillippa Gregory, author of The Other Boylyn Girl, and many other Historical novels. https://www.youtube.com/watch?v=bx3PUKEsGzk
She pretty much hits the nail on the head and she works with characters based on real people who once lived. If you’ve never watched a couple of historians debate the accuracy of a Phillippa Gregory novel, you really should pop over to YouTube more often. It makes a point, Historical Fiction brings the dead back to life. And you’ll feel it when these historians argue about Anne Boylyn as if she was still alive and major player in our political world today. She’s been dead 500 years now. http://www.philippagregory.com/biography
P.S. I love Phillippa’s novel, but I cannot watch the movie version of it. No matter how much I also love Scarlet Johannsen as an actress. For me, the novel is about Mary Boleyn and it’s awesome. But, there can be only one Anne Boleyn for me and that’s Natalie Dormer playing her in The Tudors. http://www.sho.com/the-tudors