Looking sharper than usual in a jacket and trousers that actually match, Jeremy Corbyn cut a dapper figure as he left his home the morning after Theresa May surprised everyone by calling a general election.

As he left via the front gate of his wisteria-clad £600,000 terraced home in Islington, North London, onlookers could almost have been forgiven for thinking that he might have been taking style tips from the stylish younger man, one James Schneider, striding along so purposefully beside him.

The next morning, there was Mr Schneider again, clutching a sheaf of papers, as dapper Mr Corbyn (not a vest or bicycle clip in sight these days, it seems) headed out to deliver a speech to launch Labour’s general election campaign.

James Schneider grew up in Primrose Hill, one of London's most exclusive neighbourhoods, before going to Winchester College and Oxford University

As they left Church House in Westminster later, Mr Schneider was seen again, keeping a watchful eye on his new 67-year-old boss as he faced the camera crews.

So, you may well ask, just who is James Schneider? Well, since October 2016 the 29-year-old, who was privately educated and grew up in a house now worth £7million in Primrose Hill, one of London’s most exclusive neighbourhoods, is in fact ‘head of strategic communications’ for Mr Corbyn. Just six months into the job, he finds himself a key member of the Labour leader’s team as they prepare for June 8.

His father Brian Schneider was a financier who died aged 48 in 2004.

His mother Tessa Lang, 61, is a London-based property consultant who, according to her profile on the business networking website LinkedIn, has ‘facilitated sales and bespoke property search and acquisition in many of London’s most exclusive urban villages’ including Kensington, Notting Hill, Primrose Hill, Bloomsbury, and Hampstead.

She is a member of The Sloane Club, a private members’ club in Chelsea, and ‘an occasional contributor of poetry to The Spectator magazine and others’.

Mr Schneider's mother Tessa Lang is a member of The Sloane Club, a private members’ club in Chelsea, and ‘an occasional contributor of poetry to The Spectator magazine and others’

James Schneider attended top public school Winchester College.

He then went up to Trinity College, Oxford, where he was president of the Liberal Democrats student branch, and was neither a Labour voter at the last election nor a party member.

He left the Liberal Democrats in 2010 – and joined the Labour Party on May 11, 2015, four days after Labour’s last crushing general election defeat.

He describes himself as having been an ‘African-focused’ journalist for five years, including posts as editor of an online news analysis website on Africa and a spell on a magazine. But he first hit the headlines himself as a founder of the pro-Corbyn grassroots movement Momentum. The organisation was set up in October 2015, four weeks after Mr Corbyn was elected leader.

The movement says it ‘exists to build on the energy and enthusiasm from the Jeremy Corbyn for Labour Leader campaign, to increase participatory democracy, solidarity, and grassroots power and help Labour become the transformative governing party of the 21st century’. Mr Schneider was a national organiser and press officer for Momentum.

Schneider first hit the headlines when he helped found the pro-Corbyn grassroots movement Momentum in October 2015

He left that role for his new job under Mr Corbyn. He was appointed the Labour leader’s head of strategic communications in October 2016, a month after Mr Corbyn swept to his second leadership election victory.

He works under Seumas Milne, the former Guardian journalist who is overall chief of the leader’s press team. His role was boosted last month after Mr Corbyn’s spokesman Matt Zarb-Cousin stepped down. Mr Schneider has stepped into his shoes, briefing the media on Labour policies.

He is also tasked with advising Mr Corbyn on media strategy and the best way to sell his Left-wing policies (but no one would comment on whether his duties also include advising Mr Corbyn on appearance and dress sense). Activists at Momentum’s Hackney branch recently suggested an idea to help win the General Election, saying: ‘The odds are against Labour, but if enough of us bet a tenner on Labour to get the most seats or Corbyn to be the next PM, the odds will shorten and the narrative will begin to change.’

Mr Schneider is still a member of Momentum but is no longer responsible for handling inquiries about the group so would not comment on the idea. But a Momentum spokesman explained: ‘Activists from Hackney Momentum made a light-hearted suggestion that putting £10 on Labour would help shift the media narrative and encourage reporting on actual policies, to enable voters to make an informed decision on 8th June.’ But Mr Schneider’s elevation to Mr Corbyn’s inner circle shows how Momentum has become increasingly influential.

Schneider's childhood home is now worth an estimated £7million

‘It’s hard to know where the leader’s office ends and Momentum begins,’ one insider said. ‘Momentum is Jeremy Corbyn’s “praetorian guard” and there has been a fairly seamless exchange between Momentum and Corbyn’s office in Westminster. James Schneider’s appointment is symptomatic of that. He was credited as the architect of Mr Corbyn’s re-election victory last year, and now he is in the leader’s office.’

Another insider said: ‘He is a posh boy with a burning ambition to promote himself. He has an uncanny ability to make sure he is in every shot with the leader, with his hair perfectly tousled.

‘He is part of that legion of public school Oxonians who are at the very heart of that operation. Schneider fits into that mould of the type of person the man in charge likes. Corbyn likes people around him he thinks are clever because it makes him feel clever.’

Mr Schneider declined to comment yesterday.

But a Momentum source claimed references to his wealthy background were ‘a smear used to undermine someone campaigning to make sure that wealth and power rests with the majority, rather than hoarded by a few at the very top’, adding: ‘James is professional, highly competent and well-liked by journalists and activists alike.’