Henry Bolton has been ousted as Ukip leader after party members backed a motion of no confidence in him.
At a crisis meeting in Birmingham, activists voted by 867 to 500 to express their lack of faith in his ability to lead the party.
The move now leaves the party facing a further period of uncertainty, with Mr Bolton forced out after only being elected in September last year.
Mr Bolton had attempted to cling on to the leadership despite a no confidence vote by the ruling national executive committee (NEC) and a revolt by several senior figures in the party in protest at his relationship with model Jo Marney.
Mr Bolton said he still has "strong affections" for his former girlfriend who sent offensive messages about Meghan Markle, and compared the scrutiny of his private life to that faced by Diana, Princess of Wales.