Can an author use a name if the character is famous?
I am sure many of you have read stories with characters named Sam, Mary, Ann, Joe, Eddie, and such. They are author’s stable names.
Yes, they can be used if it is an ancient or common name. Not a name the author invented. I used the name Hermione in a story long before Harry Potter hit the market. I got the name from mythology. It’s the name of an ancient Greek deity. You can’t trade mark ancient names. You have to originally create the name or word or phrase in order to own it. You can’t take a popular cultural sayings, idioms, and phrases say it’s yours. You can’t own it when people have been saying it for decades, centuries. The same applies with names.
My Hermione isn’t a witch nor attending a magical school. She’s an immortal just as some myth says she is.
You may asked: Can’t you change the name since there’s a character wearing the same name and has already made it famous?
No, not unless I’m willing to change the entire story, the theme and her relations to the other characters. Change the character’s attributes and powers as well. That’s a lot of work.
If you want to change the name of a character after discovering another author has made it famous, it’s up to you. But remember to erase all dialogues and references to the old name. Keep the name and characteristics in line with the consistency of the story.
In Greek mythology, Hermione was the daughter of Menelaus, king of Sparta, and his wife, Helen of Troy.