Who is Jeremy Corbyn? An international reader’s guide to the little-known British politician who could become Labour's leader

An extraordinary political tale is unfolding in Britain: a little-known politician, relegated to the margins of his party for much of his career, is now the favourite to become leader of the Labour party, the second-largest party in Britain and the government’s main opposition.

Jeremy Corbyn has been addressing increasingly sizeable audiences across the country, enthusing young new voters and Labour veterans alike with his anti-austerity, leftwing message declaring that the current economic and political status quo is neither inevitable nor desirable.

This stands in stark contrast to his rivals in the contest to succeed Ed Miliband, the Labour leader who presided over a huge loss for his party at the election in May.

Corbyn’s fellow candidates Andy Burnham, Yvette Cooper and Liz Kendall are struggling to convince potential voters that their moderate policies are what the party needs to win back power from the Conservatives in five years’ time.

Meanwhile, senior Labour figures have warned of the “madness” of a Jeremy Corbyn-led party. The former Labour prime minister Tony Blair, who led the party to three election victories, had a simple message to those whose heart was being swayed by Corbyn: “Get a transplant."

Corbyn is not a sexy politician. Member of parliament for a north London constituency since 1983, he is neither a fresh new face on the national scene, nor a striking orator with a magnetic presence. This is not Britain’s Alexis Tsipras. He is an understated, thoughtful politician, happier to talk policy or discuss the people behind him than to focus on his own personal importance. Age 63, bearded and soft-spoken, Corbyn has attracted mocking headlines for his beige clothing and vests bought from the local market.