Sauron the lord of gifts yes.
funny thing though is that Khamul the easterling a ringwraith used to be as his name suggests a man of Rhun, and even knowing that the present Khan of Rhun followed in his footsteps down the same foolish path.
maybe the Haradrim are just so over confident about thier mumakill that they have nothing to fear. i mean come on look at this guy
http://lotr.wikia.com/wiki/M%C3%BBmakil_Mah%C3%BBd
edit: btw just realized that wiki page reads like it was written by a three year old