In November 2015, just two months after his landslide victory in the Labour leadership election, Jeremy Corbyn found himself immersed in a controversy on Remembrance Sunday (marking the contribution of World War service personnel).

Mr. Corbyn, whose anti-monarchist, anti-conflict views already had many of Britain’s tabloids in a tizzy, was lambasted for supposedly refusing to bow as he laid a wreath at the ceremony. It subsequently emerged that not only had he done so but he had also stayed on after the ceremony to talk to veterans, while other politicians attended a meal for VIPs.

Why the attacks on Mr. Corbyn?

British politics has long been infamous for the personal nature of media attacks on leaders, but the hostility faced by Mr. Corbyn has been something else. It’s been driven in part by his steadfast refusal to play ball with the mainstream media — he doesn’t take press questions after every public speech, and often ignores questions out of the context of a planned interview, often preferring to respond to criticism on his own terms, through social media. He doesn’t wheel out his family for photo opportunities. He’s made a point of focussing on talking to people directly, as was the case with his first performance at Prime Minister’s Questions in 2015, when he relied on questions gathered from the public. An avowed socialist, he has no qualms talking about re-nationalising infrastructure or raising taxes on businesses and the wealthy, an approach shunned by Labour since the days of Tony Blair. He doesn’t even look like many think a politician should: his trademark beard came well before fuzz became fashionable while his casual, sometimes maverick, dressing style had some Conservatives seething when he first entered Parliament.

How did he get to where he is?

Born to peace activists, Mr. Corbyn was involved in politics from a young age, as an early member of the Campaign for Nuclear Disarmament, a volunteer in Jamaica, and a trade union organiser. He entered Parliament in 1983, representing the London constituency of Islington North, which he has held to date. His radicalism continued in Parliament — he was arrested outside the South African embassy demonstrating against apartheid, brought striking miners into the House of Commons, and invited former Irish Republican Army prisoners to the Commons. His journey to the Labour leadership was just as unconventional.

He reluctantly agreed to run, after others insisted they’d had their turn, and just managed to scrape together the necessary number of nominations from other Labour MPs to stand, including from those who saw him as a political no-hoper but wanted a token left-wing candidate.

Rebel or man of principles?

His detractors denounce him as a rebel (he voted against the party whip over 400 times while Labour was in power, between 1997 and 2010), but to his supporters he is a deeply principled politician, willing to stand up to the party, and his family, when those values are on the line.

His opposition to grammar schools, a selective form of state school to which his second wife hoped to send one of his sons, cost him the marriage. He was probably the most prominent parliamentary campaigner against the war in Iraq. He’s also been an active local MP, taking up issues raised with him by campaign groups, such as a commitment to eliminating caste discrimination. For years, he chaired Britain’s Dalit Solidarity Network. He’s been an active member of global socialist networks, attending the 2004 World Social Forum in Mumbai. He has pledged to work with socialist groups across Europe as Britain faces up to Brexit. In 2013, he won the Gandhi Foundation’s International Peace Award.

A liability or an asset?

Some of the causes he has championed have made him easy prey to nationalist hysteria. Leading the party has also forced him to compromise on others, such as on Britain’s nuclear deterrent. However, as he has developed in stature as a leader he has sought to turn some of his perceived vulnerabilities on their head. Mr. Corbyn attacked Britain’s foreign policy, just days after the Manchester atrocity, appealing to the very soldiers the right-wing media had accused him of betraying, with a promise not to send them into futile wars.