Henry Bolton has been elected as the new leader of UKIP in a shock result.
The little-known candidate beat the two front runners in the contest - Irishwoman anti-Islam campaigner Anne Marie Waters, and London Assembly member Peter Whittle - to win with 3,874 votes.
He told the party members: "Brexit is our core task, however, it is not the end of the line."
The former army officer warned earlier this month that UKIP was in danger of becoming the "UK Nazi Party" if it picked the wrong leader to succeed Paul Nuttall, in comments which appeared to be aimed at Ms Waters.
In his victory speech at the party conference in Torquay, he called on members to rally around the party.
"Without being united, we cannot lead," he said.
The party has struggled to find its feet since Nigel Farage quit, and its vote share fell to 1.8% at the general election, from 12.6% in 2015.
12,915 votes were cast in the leadership election, a 46% turnout.
Mr Whittle, who had been touted as a likely winner, came a surprise fifth with 1,413 - an 11% share of the vote - while Ms Waters came second with 2,755 votes, a 21% vote share.
Up to 18 of the 20 UKIP MEPs had been reportedly preparing to quit the party if Ms Waters had won the leadership battle.
Mr Bolton called on the party to unite behind him to allow him to deliver its aims.
He said: "I do not see myself now as simply being your leader, I see myself as serving this party. You are the party, not me, and this party needs to serve its country.
"There is no greater calling than that and I would call on all of you, whether you voted for me or not, to rally around the party, to be united."
Mr Farage said he was "delighted" Mr Bolton had won the leadership battle.
"He is a man of real substance," the former leader added.
Meanwhile, Britain’s Premier League soccer body is believed to be consulting its lawyers over accusations that UKIP’s new logo is a "rip-off" of the emblem of English football's top flight.
