"Mr Corbyn, who began the contest as a rank outsider, saw off a challenge from frontbenchers Andy Burnham, Yvette Cooper and Liz Kendall.
"He gained 251,417 or 59.5% of first preference votes - his nearest rival, Mr Burnham, got 19%.
"Ms Cooper was third on 17% and Ms Kendall a distant fourth with 4.5% of the vote."
"I say thank you in advance to us all working together to achieve great victories, not just electorally for Labour, but emotionally for the whole of our society to show we don't have to be unequal, it doesn't have to be unfair, poverty isn't inevitable," Corbyn said after his victory.
"They are fed up with the inequality, the injustice, the unnecessary poverty. All those issues have brought people in, in a spirit of hope and optimism," he said.
Reuters notes that "Corbyn has struck a chord with many Labour supporters by repudiating the pro-business consensus of former Labour leader Tony Blair and offered wealth taxes, nuclear disarmament and ambiguity about EU membership."
The news agency adds that his election "reflects growing popular support for left-wing movements across Europe, with Syriza taking power in Greece and Spain's anti-austerity party Podemos performing well in opinion polls.
"Corbyn's rise also has an echo of the way Senator Bernie Sanders has galvanized left-leaning Democrats in his bid to beat Hillary Clinton to the party's nomination for the U.S. presidential race," Reuters says.