Sam Raimi originally intended his name to be Ash Holt when making the first Evil Dead, of course, he didn't actually put that in the movie. Later he decided to change it while writing AOD I believe. The full official name, as of current, is actually Ashley J. Williams.
By the way, did you know Raimi is writing the script for a fourth one? Jeez I can't imagine another one since Campbell is getting old.