Harry and Meghan’s first post-Megxit appearance last week was at an event held by a US banking giant that has been embroiled in a succession of controversies.

JP Morgan was among the group of big American investment banks blamed for triggering the financial crisis just over a decade ago – and was eventually ordered to pay a then-record $13 billion fine – about £10 billion – in 2013 for misleading investors in the years leading up to the meltdown.

Coincidentally, 2013 was also the year the bank finally parted company with one of its most notorious clients, paedophile financier Jeffrey Epstein.

In 2013 the bank finally parted company with one of its most notorious clients, paedophile financier Jeffrey Epstein (pictured)

Bank insiders have claimed that concerns were raised about Epstein – a friend of Prince Andrew – after the financier was charged with sex crimes and pleaded guilty to soliciting a minor for prostitution in 2008. Yet he remained a JP Morgan client for another five years. One theory of why the disgraced American – who died in jail last year – was kept on in the face of increasingly lurid allegations was his value to JP Morgan.

Epstein is said to have arranged business introductions for one of his contacts at the bank, Jes Staley, the head of private banking who would later become chief executive of Barclays bank in Britain.

The Mail on Sunday revealed in 2015 that Epstein lobbied for Staley to secure the top job at Barclays after 34 years at JP Morgan. Staley has said he had no knowledge of Epstein’s illegal activities and Barclays has denied its directors were approached by Epstein.

Among JP Morgan’s other notable former clients is Bernie Madoff – the fraudster behind the biggest Ponzi scheme in history.

JP Morgan was among the group of big American investment banks blamed for triggering the financial crisis just over a decade ago. Pictured: A jet owned by JP Morgan

Traders at the Wall Street Stock Exchange during the collapse of Lehman Brothers Holdings in 2008

According to court documents made public in 2011, senior JP Morgan executives had started to doubt the legitimacy of Madoff’s investment activities but continued to do business with him.

JP Morgan eventually paid a $2.5 billion fine for failing for two decades to report Madoff’s suspicious dealings. He was jailed for stealing from wealthy investors – including a number of celebrities – over more than 20 years. Losses from the scheme are said to have hit $17 billion.

JP Morgan admitted it could have done a better job of handling concerns about Madoff’s activities but said no employee knowingly assisted with the fraud.

At the helm of the bank through the good times and the bad has been highly regarded chief executive Jamie Dimon.

Since taking the top job in 2005 he has become known as The King of Wall Street, raking in $298.8 million in pay and perks.

Among JP Morgan’s other notable former clients is Bernie Madoff – the fraudster behind the biggest Ponzi scheme in history

Last month, the 63-year-old became the best-paid banking chief for a fifth year in a row by scooping more than £24 million.

He is credited with steering JP Morgan through the financial crisis to become the most profitable bank in the US today.

Nicknamed ‘Mad Dog’ at private school in New York – ostensibly for his prowess on the sports field – he has an MBA from Harvard, where he met his wife, Judy.

They married in 1983 and have three grown-up daughters – Julia, Laura and Kara.

It’s fair to say Dimon hasn’t struggled to find ways to spend the wealth he has accrued since his university days. As well as a home on Park Avenue, one of New York’s most prestigious addresses, he and Judy escape in the summer months to their 34-acre country home about an hour’s drive north from central Manhattan.

The 9,600 sq ft 1930s mansion nestles in woodland near the town of Bedford, where other wealthy homeowners include former New York Mayor Michael Bloomberg and actor Michael Douglas. Dimon bought the summer retreat in 2007 for a reported $17 million.

His style of management is said to be fierce. It has been claimed he likes to punch the air when he raises his voice to berate staff and carries a crumpled piece of paper containing the names of ‘the people who owe me stuff’.

The Duke and Duchess of Sussex may have pocketed $1 million for their first post-Megxit appearance. Pictured: Couple in Cape Town, South Africa in September

Harry, pictured at a charity event in London last month, spoke of his battle with mental health at the summit in Miami on Thursday

His tight grip on JP Morgan has not stopped the bank coughing up more than $31 billion in regulatory fines since the 2008 crisis for offences ranging from manipulating energy markets to accusations of racial discrimination.

In January 2017, JP Morgan agreed a $55 million settlement over allegations that it charged black and Hispanic mortgage borrowers higher rates than its white customers.

It denied the accusations, made by the US Justice Department, but agreed to settle.

JP Morgan has also issued a grovelling apology and paid millions of dollars in reparations for historic links to the slave trade.

In 2005, it admitted that two Louisiana banks that were later absorbed into the company once held 13,000 slaves as collateral and owned 1,250 slaves.

JP Morgan’s London office reported a $2billion trading loss in 2012 that was traced to big bets taken by a group of traders led by Bruno Iksil, known as the London Whale.