But on Saturday, 33-year-old Sheikh Rashid was laid to rest after apparently dying of a heart attack at home on Friday.

Now, Daily Mail Online can reveal that the untimely death of Sheikh Rashid has left many questions unanswered - in particular what caused an apparently healthy man to die at such a young age.

Although the official cause of death has been given as a heart attack, allegations of drug and steroid abuse and of several stints in rehab have long percolated through Emirati society circles.

Rashid, who at one point held a number of high profile roles, quietly withdrew from public life in the years leading up to his death and became an enigmatic figure in the emirate he was once destined to rule.

Born in November 1981, Rashid was the son of Dubai's ruler Sheikh Mohammed and his principal wife, Sheikha Hind bint Maktoum bin Juma Al Maktoum.

Sheikh Mohammed is a modernizer, albeit one with two wives and 24 children, and has transformed what was once a dusty patch of sand into a glittering modern metropolis.

He has also parlayed what was a small trickle of oil into tourist dollars, making Dubai, with its mega-malls and year-round sunshine into one of the top tourist destinations in the Middle East.

Through his Godolphin racing stable, Sheikh Mohammed is a prominent figure in the horse world and regularly attends prestigious race meetings such as Royal Ascot in Britain.

Sheikha Hind, by contrast, is almost never seen. The 53-year-old first cousin of her husband, she is known as 'the First Lady of Dubai' and is mother to 12 of his children.

Aged 17 when she married Sheikh Mohammed, Hind's wedding, estimated to have cost $100 million, was Dubai's first big public event.

But unlike Princess Haya of Jordan, Sheikh Mohammed's junior wife, Hind chose to become a traditional Arab matron and lives sequestered in accordance with the Islamic purdah system.

Men such as Sheikh Rashid, however, are not subject to purdah which made his low profile all the more mystifying to locals.

Provided with a princely education, Rashid's academic career began at the prestigious Rashid School for Boys in Nad Al Sheba.

Later, he moved to the UK to attend Sandhurst – a top training college for British military officers – before graduating in 2002.

On his return to Dubai, he assumed an increasingly high profile and took on a number of prominent public roles, as well as partnerships in a series of lucrative businesses.

He also opened a number of his own companies, among them United Holdings Group Dubai – a multidisciplinary investment group.

Like his father and brothers, he was also a passionate horseman and set up his own racing stable under the name of Zabeel Racing International.

With a personal fortune of an estimated $1.9 billion, he had no shortage of funds to invest and soon racked up an impressive number of winners – 428 in total.

He also developed an interest in endurance racing, the equestrian equivalent of the marathon, and in 2006, became a national hero when he picked up two gold medals at the Asian Games.

But less than a year later, Sheikh Rashid had all but disappeared from public life – and, in 2008, was stripped of the title of crown prince.

A third brother, Sheikh Maktoum bin Mohammed Al Maktoum, 31, was given the title of deputy ruler of Dubai at the same time. 

Quite why this should have happened remains unclear, with the official explanation being that the current incumbent Hamdan, 32, was simply better suited to the job.

That, however, was not the explanation bandied about in the upper echelons of Emirati society at the time or, indeed, as it later became clear, among the diplomatic community.

One particularly lurid version of events appeared in a confidential memo written the then Acting Consul General David Williams for the CIA the same year.

The diplomatic cable was one of thousands released by Wikileaks and offers a fascinating insight into what really went on behind the scenes at the Zabeel Palace.

Noting that the move wasn't a complete surprise because of Hamdan's increasingly high profile, Williams went on to say that Rashid 'does not play a public rule in Dubai affairs'.

(dailymail.co.uk)