Nick Griffin said his election was a "massive breakthrough"
Nick Griffin, the leader of the British National Party (BNP), has become one of the north west of England's eight MEPs.
The Conservatives retained three seats, but Labour lost one, leaving the party with two. UKIP and the Liberal Democrats each held onto one seat.
The BNP won 8% of the votes across the the North West, although its share in Cumbria was slightly lower at 6.7%.
MEPs and candidates staged a walkout as Mr Griffin began his victory speech in Manchester Town Hall.
Anti-BNP campaigners chanted "black and white to unite" and "smash the BNP", while dozens of police officers patrolled the area.
Mr Griffin said his party was "the most demonised and lied about" in Britain.
Throughout the UK, Labour gained just 15.3% of the vote, and was beaten into third place behind the Conservatives and UKIP.
The party was more popular across the North West, with 20.4%, although in Cumbria its share fell to 15.8%.
Conservatives topped the poll with a 29% share in Cumbria and 25.6% in the North West as a whole.
The BNP came fifth after the three main parties and UKIP.