Killian later claimed that he was the real Mandarin, but outside of having some dragon tattoos, there was nothing about him that screamed true Mandarin.
In case you need a refresher, the Mandarin the world was introduced in Iron Man 3 was actually just a drunken actor named Trevor Slattery who the movie’s real villain, Aldrich Killian, hired to take responsibility for the ‘attacks’ across the world, when the destruction was actually being caused by Killian’s Extremis experiments.