Michael Caine, whose birth name is Maurice Micklewhite, legally changed it to his stage name after years of airport security confusion in the age of terrorism. Caine is an easily recognizable international actor, so when he would hand over his passport with the name "Maurice Micklewhite," it would confuse airport security and cause him delays.
He told The Sun the real culprit behind long airport security lines, saying "I changed my name when all the stuff started with ISIS and all that."
It's understandable that airport security got confused when they saw Michael Caine, but were handed a passport with the name of a 19th century British chimney sweep. Caine actually chose his stage name after seeing a movie poster.
He was in a phone booth on a call with his agent, looked up and saw a poster for the 1954 Humphrey Bogart film The Caine Mutiny:
I was opposite the Odeon and I looked up, and my favorite actor is Humphrey Bogart, and there it was.
Everyone already hates ISIS for the obvious reasons, but now they've gone too far. Nobody messes with Sir Michael Caine and gets away with it. Nobody.