On March 26, 1981, an 11-year-old schoolboy stood up to address the annual general meeting in London of Lonrho, one of the largest conglomerates in the world.

Was it really sensible, the precocious interrogator asked from the floor, for Lonrho to make a bid to buy the failing Observer newspaper?

And, if the purchase went ahead, what plans were there for making it profitable?

As Lonrho's chairman, it fell to Lord Duncan-Sandys, a former Conservative Minister, to answer the child.

This was a shareholders' meeting, after all, and the boy's question had to be treated as respectfully as anybody else's – even if he was accompanied by his nanny.

Duncan-Sandys confirmed that there were indeed plans in hand, but in view of an ongoing inquiry, he was unable to reveal them.

A 12-year-old Jacob Rees-Mogg reads the Financial Times. Obsessed with making money, the same year he addressed shareholders at a General Electric Company meeting

Rees-Mogg and his wife Helena De Chair at the Conservative Party Conference 2013 in Manchester

Rees-Mogg, pictured in the chamber in his role as Leader of the House of Commons, had a long career in finance before becoming an MP

If the chairman had been in any doubt as to the identity of the youth who put him on the spot, he was soon made aware of it: Jacob Rees-Mogg.

It was the first of many occasions on which this now-familiar name would appear in the newspapers, with several national titles reporting the incident the following day, along with the fact that the young entrepreneur owned 340 shares in the firm.

A few months later, Rees-Mogg, by now 12, was in the spotlight again, this time at the annual general meeting of the General Electric Company (GEC).

'What is the point of having such a pathetic dividend,' asked the young Jacob, 'when you have made a profit of £476 million and have total reserves of £1,388 million?'

His actions, although extraordinary for one so young, were a foretaste of what was to come – a glimpse of his eventual character in embryonic form.

By the time he made his infamous speech at the GEC meeting, Rees-Mogg had already been fascinated by the idea of making money for more than half his young life.

Tim Williams, son of the Labour peer Lady Falkender and a contemporary at Rees-Mogg's prep school, Westminster Under School, remembers: 'Jacob used to sit behind me and read the Financial Times [aged eight]. I don't remember him being interested in politics – I mostly remember him being interested in finance.'

Indeed, it was just before his first year at the school, aged seven, that the young Jacob was finally able to open his first bank account.

He had tried to do so at six but was not permitted to because of his tender years.

Later, following his Lonrho appearance, he was interviewed by the Evening Standard about his hobby of buying and selling stocks and shares.

It had begun, he said, a few years earlier when he had inherited some shares and £50 from a distant relative. (In fact, his father William Rees-Mogg, a former editor of The Times, is said to have made his first investments on his behalf.)

In December 1981, Jacob, by then 12, told the Daily Express's Jean Rook: 'I like playing with money. I love the stuff. I want more and more of it.'

Explaining what he did with his gains, he told her: 'I keep it. I've always loved money as money, not for what it buys. Don't ask me why, because I don't know the answer to it.'

He also confided that he planned to be a millionaire at 20 and a multi-millionaire at 40. While the first of these aspirations was not met, the second most certainly was.

Some believe that the financial security given to him by his marriage to heiress Helena de Chair emboldened Rees-Mogg to take the gamble of his professional career

Rees-Mogg's financial acumen had already been strongly in evidence that autumn. Having agreed to an interview with Radio 4's Today programme about his financial aims, he had first – impressively – negotiated a fee for his appearance of £18. But eight weeks later there was no sign of the payment.

In November, he fired off a letter of complaint. 'Dear Today programme,' wrote the 12-year-old.

'You are in a debt of £18 which was payable as from 13/9/81. I have no idea what your excuse is but I will not accept it. If it is not recived [sic] by the 10/11/81, which is nearly two months, I shall increase it to £36. If still not recived [sic] within ten days I shall take legal advice.

'I hope it does not come to that for I have no desire to prosecute the BBC.'

Despite the BBC's amusement, the fee was quickly sent to him.

Later, at Eton, the teenage Rees-Mogg's interest in generating money was unabated. Contemporaries remember that he would regularly telephone his stockbroker at lunchtime.

In 1982, 12-year-old Rees-Mogg told an ITV documentary, Rowan's Report, which featured talented children: 'I get £1 a week, which is paid annually by my father at the beginning of the year, which means I can get the interest from a bank on the money he pays me for a year rather than getting it in dribs and drabs where the interest is less.'

He also reads the catechism to his six children over lunch every Sunday as a way of passing on to them the teachings of the Church

Asked by presenter, Wingham Rowan, about his parents' attitude to his fortune-building, he said, 'They think it's a jolly good idea for me to make my own money, and for me to make as much of it as I can.'

As Rees-Mogg's close friend and business partner Dominic Johnson explains: 'There is always this view that he comes from this ultra-rich, privileged background. Clearly, in relative terms, he's privileged, but he's not rich. His father was never rich. His father made money out of being a journalist.'

A final question before the credits rolled on the Rowan's Report interview could prove to have elicited the most telling answer of all.

Asked about his ambitions, the schoolboy answered: 'Well, I'm going to continue buying and selling shares. And I'd like to be Prime Minister at the age of 70.'

When he left Oxford with a 2:1 in History in 1991, Rees-Mogg was open with friends about his desire to go into politics, but he was equally candid about wanting to make plenty of money first.

As a first step towards his goal, he joined J. Rothschild Investment Management in London as an analyst.

Since their marriage in 2007, Jacob and Helena Rees-Mogg have also bought two properties in which they live

Based in offices in St James's Place, near Green Park, this was unquestionably a plum post for a man aged 22 whose only obvious qualification was a youthful interest in playing on the stock market with his pocket money.

What undoubtedly helped his chances was the fact that his father was a long-standing friend of the firm's founder, Lord Rothschild.

That William Rees-Mogg had himself been on the board of the company since 1987 cannot have done any harm to his son's prospects either.

But the younger Rees-Mogg worked at J. Rothschild for barely two years before moving to Lloyd George Management in Hong Kong.

William's influence was again evident in helping his son to secure this post, in that it was his personal relationship with the firm's founder, Robert Lloyd George, which undoubtedly smoothed the path.

Jacob, who had no professional qualifications, did not have to make a formal application or undergo an interview process.

More than 25 years later, some people with knowledge of the appointment insist that Lloyd George took Jacob on only as a favour to William.

In the summer of 1996, Rees-Mogg returned to work in the company's London office.

Still only in his mid-20s, he lived first in a flat in Pall Mall and then in a set of rooms at Albany, a Georgian building in Piccadilly regarded as one of London's most exclusive addresses.

Later, he moved with his younger sister Annunziata into a Grade II listed four-bedroom house in Park Street, Mayfair, which he subsequently bought in 2004 for £757,000 with a mortgage from Coutts, the private bank.

On moving in, one of his first acts was to ask the telephone company to change the last four digits of his landline number to '1649' to commemorate the year in which Charles I was executed.

If brother and sister were not entertaining friends at home, Rees-Mogg would often meet friends in nearby Claridge's hotel.

Wedding day row with his boss over a bonus? There is a story – denied by Jacob Rees-Mogg – that in the receiving line at his wedding reception in January 2007 he had an argument with one of his bosses from Lloyd George Management. His alleged gripe related to what he perceived to be the unacceptably small bonus that he had just been awarded. It seems highly unlikely that this scrupulously polite stickler for good form would choose to remonstrate with a senior colleague over a matter of money in front of people at his own wedding. And yet the impression of one witness is that while guests mingled over champagne and canapes, Rees-Mogg was involved in an exchange of words with one of his managers and that the conversation related to work. This witness says it was pointed out to Rees-Mogg that his wedding reception was not the place where business should be aired. He says: 'I said to Jacob, 'This is not the time to talk about it… This is not a day on which you should discuss work.' ' This clash appears to have had far greater resonance than perhaps anybody realised that day, however, and almost certainly contributed to Rees-Mogg's decision not long afterwards to resign from LGM and establish his own boutique investment house. Advertisement

One regular social acquaintance says: 'When the Rees-Moggs entertained, which they did regularly, it was always impeccable.

'Embossed invitations would be sent, and every known politician was invited. If I met Jacob alone, drinks were usually in Claridge's, where he had his own table, and consisted uniquely of champagne.'

Given that Rees-Mogg was barely 30 when he began living in his desirable four-bedroom house in Park Street, there is no doubt that his professional life was at this point in the ascendancy.

As a fund manager looking after a variety of portfolios, Rees-Mogg had been considered to be performing well after 14 years with LGM and was by this point, say former colleagues, paid a salary and bonus totalling about $2 million.

But there had been at least one expensive – and deeply embarrassing – mistake along the way which arguably raises questions about his eye for detail.

According to some of his former colleagues, it occurred in 2005, two years before Rees-Mogg left the firm.

At that time, LGM held stock in the media company Endemol via one of the portfolios it managed for an American client.

When Endemol was the subject of a takeover by the Spanish giant Telefonica, LGM should have either accepted Telefonica's offer or sold the Endemol shares on the open market while they were still listed.

Neither of these things happened.

As a result, the Endemol shares which LGM looked after were almost worthless. Robert Lloyd George himself had to fly to Madrid to try to persuade Telefonica to buy them out, but the Spanish firm refused.

As Rees-Mogg was the portfolio manager, this was a serious oversight, which, former colleagues say, Lloyd George believed ultimately was attributable to him.

Fortunately, LGM was able to rely on its insurance policy to cover the estimated $4 million that this error cost.

One former colleague says: 'Had this episode happened in another company, Jacob would have been let go. It was something he hadn't paid attention to. But Robert forgave him.'

In March 2007, a few weeks after returning to work following his honeymoon, Rees-Mogg, along with colleagues Dominic Johnson and Edward Robertson, attempted to stage what amounted to a coup at LGM, in which Rees-Mogg appears to have been the prime mover and was certainly the frontman.

Among the trio's concerns was the sense that Lloyd George ran the business with too heavy a hand and did not distribute enough of the equity of the company in staff bonuses.

Posh? His grandad was a lorry driver It's often assumed that with his double-barrelled name, well-spoken tones, Eton and Oxford education and double-breasted suits, Jacob Rees-Mogg is upper class or even aristocratic. Yet on the British social scale, this is wide of the mark, as he would no doubt be the first to acknowledge. When the broadcaster Andrew Neil asked him in 2010: 'So, what class are you?' Rees-Mogg blushed slightly and replied: 'I'm a man of Somerset.' Certainly his forebears never owned a great estate, nor a hereditary title. He has been privileged, but that is different from being born into great prosperity or being truly 'posh'. Over the years Jacob Rees-Mogg has said very little about his mother Gillian's family. But archival research has shown that when his grandfather Thomas Morris married his grandmother Eileen in 1934, the former was a milk contractor in Ilford, Essex. Thomas's own father – Jacob's great-grandfather – had been a dairyman himself. By the time Gillian was born in 1939, her father had left the milk business and, according to a census of the time, was a 'motor lorry driver' at the outbreak of the Second World War. He later became a sales representative at a company called Car Mart, based in Euston Road in Central London. Public records show that Gillian's mother's family, whose surname was Shakespeare, worked in a variety of manual jobs. Her grandfather, Jacob's great-grandfather, Christopher Shakespeare, was a printer and compositor who lived in Northern Ireland at the time of the 1911 Census. Friends of the Rees-Moggs are united in their praise for Gillian and speak fondly of her as a 'brilliant mother' and 'lovely woman' whose unwavering support for her husband William was an essential ingredient of his successful journalistic career. During his wedding speech, Jacob is said to have praised his father as 'the greatest living Englishman', while according to a guest: 'He also said he would like to say his mother was the greatest living Englishwoman, but Margaret Thatcher was still around.' Advertisement

A source says: 'He [Jacob] told me… 'We're going to offer to buy the company. We have financial backing.' And so off he went and said this to Robert.'

Rees-Mogg's radical proposal went down very badly with Lloyd George, who saw it as a 'betrayal'.

However, there was no going back. Once it was clear that Rees-Mogg's demands would not be met by Lloyd George, he left the business, along with Johnson, Robertson and several other members of staff – and set up a venture of his own, Somerset Capital Management.

Working from the basement of Rees-Mogg's Mayfair townhouse, the newly formed company began operating in earnest in July 2007.

Rees-Mogg has said that for the first few months he paid all the salaries out of his own bank account as the business got off the ground, and his pride in his subsequent achievement is palpable.

In total, it had £400 million under management in its first year. By 2010, its clients included the household of the Prince of Wales and Duchess of Cornwall.

SCM now employs 43 people in London and Singapore, and has $7 billion under management.

Even if the adage that 'business is business' is true, there is no question that Rees-Mogg's somewhat ruthless approach must have hurt Lloyd George, especially as he had shown considerable leniency by allowing his employee to take time off to contest General Elections in 1997 and 2001.

Such was his strength of feeling, he even wrote to Rees-Mogg's parents to express his regret at how their son had behaved.

Some believe that the financial security given to him by his marriage to heiress Helena de Chair emboldened Rees-Mogg to take the gamble of his professional career and leave LGM.

Others think that part of the attraction of being self-employed was his calculation that in the event of reaching the Commons, he could maintain a foot in both camps rather than having to sacrifice his lucrative career.

Now aged 50 and newly created Leader of the House of Commons, Jacob Rees-Mogg is standing at a crossroads.

He has long since achieved his goal of being a multi-millionaire. But will he, as he wished aged 12, be Prime Minister at the age of 70?

Rees-Mogg's family could be worth £200million

Jacob Rees-Mogg receives two salaries. As an MP, he is paid £79,468 plus any ministerial salary he might choose to take; as a partner in SCM he is paid approximately £180,000 a year.

The lion's share of his visible personal wealth, however, relates to his 20 per cent stake in the company.

There are several different ways to value a business of this kind, but a widely used – and conservative – method comes from applying a 7.9 per cent profits multiple.

Somerset Capital Management made profits of £34.1 million in 2017-18. On this basis, SCM is worth £269.4 million.

Of this, Rees-Mogg's holding accounts for £53.9 million.

Together with his wife, he is also a director of the UK company Saliston. Its most recent accounts show net assets of £7.7 million.

The firm's chief interests lie in London property, believed to be a Mayfair house and two flats in Pall Mall, valued by the Rees-Moggs at £7.3 million in 2018.

The accounts show that the value of the property has increased by £2.7 million during the time they have owned it.

Rees-Mogg's mother-in-law, Lady Juliet Tadgell (left), is worth in the region of £95 million thanks to her property interests in Britain and America and her extensive art collection

Saliston also holds other investments. It is not clear what these are, but they are valued at £703,000 in the 2017-18 accounts.

Since their marriage in 2007, Jacob and Helena Rees-Mogg have also bought two properties in which they live.

The first is a house in his North East Somerset constituency which they purchased outright in 2010 for £2.9 million; the second is a house in Westminster which they bought in 2018 for £5.6 million.

Taking all this into account, a conservative estimate puts the combined assets of Jacob Rees-Mogg and his wife at £70 million.

Wealth experts have told me that Rees-Mogg's mother-in-law, Lady Juliet Tadgell, is worth in the region of £95 million thanks to her property interests in Britain and America and her extensive art collection.

As Helena Rees-Mogg is Lady Juliet's only surviving child (her half-brother died in 1998 aged 36), it seems fair to assume that she will one day inherit some of her mother's estate.

Jacob and his family are, therefore, worth a combined total of at least £165 million. Ultimately, the family's wealth could plausibly exceed £200 million.

Sources close to Rees-Mogg, however, have described the figures relating to his family's wealth as 'fanciful'.

He reads his six children the catechism over lunch every Sunday

Religion occupies a central place in the life of Jacob Rees-Mogg – overriding even politics.

Friends have revealed that he has had a private chapel built at his house in Somerset, where Catholic Mass is said occasionally and which he uses as a place of contemplation.

He also reads the catechism to his children over lunch every Sunday as a way of passing on to them the teachings of the Church.

His wife is not thought to have converted from Anglicanism yet, although one friend says he believes she may do so in future.

His strong faith helped to convince Daily Mail journalist Glenys Roberts – a Conservative councillor in the West End ward of Mayfair for almost 20 years until 2018 – to ask Rees-Mogg in 2006 to be her godfather when she decided to convert to Catholicism.

Friends have revealed that he has had a private chapel built at his house in Somerset, where Catholic Mass is said occasionally and which he uses as a place of contemplation for him and his six children

At the time, she was in her 60s and he was 37, yet the age gap did not concern her in the least, however unusual it is for a godfather to be so much younger than his goddaughter.

'I got to know Jacob through local politics,' she says. 'His mother was a councillor with me for a term and he and [his sister] Annunziata, who shared a house in Mayfair, were on the ward committee.

We used to talk about Catholicism over a glass of champagne at his usual table in Claridge's.'

A further indication of the strength of his religious views lies in the fact that at a ceremony at the Brompton Oratory in London in 2009, he became a Knight of Malta, an ancient order devoted to Christian virtue and charity and involved in humanitarian issues.

To say this is an exclusive club would be an understatement. There are only 300 British Knights of Malta among a global membership of about 13,000.

His views on abortion are trenchant. He opposes it entirely, describing it as 'morally indefensible'.

He told a TV interviewer in 2017: 'With same-sex marriage, that is something that people are doing for themselves.

'With abortion, it is something that is done to the unborn child.'

He then confirmed that he is opposed to abortion even if a woman has been raped or subjected to incest, explaining: 'Life is sacrosanct and begins at the point of conception.'

Abridged from Jacob's Ladder: The Unauthorised Biography Of Jacob Rees-Mogg, by Michael Ashcroft, published by Biteback at £20. Offer price £16 (20 per cent discount) until September 30. Call 01603 648 155 or go to mailshop.co.uk.

