Cameron: The man who lost the Brexit gamble

Cameron, a former public relations adviser, called the referendum as a way of uniting his Conservative Party, betting that he would win easily with the powers of persuasion that won him two elections.

But he, and the rest of the pro-EU camp, lost the June 23 vote and Cameron announced his resignation as prime minister within hours.

He handed power to Theresa May the following month.

After the gruelling referendum campaign that divided his party and the country, Cameron appeared relieved when he stood down as prime minister.

He hummed a tune to himself as he walked away from the cameras outside his Downing Street residence.

Monday marked the finale for a star political career in which Cameron was widely praised for giving his party a wider centrist appeal, ending 13 years of Labour government with his first victory in 2010.

The son of a stockbroker, Cameron was educated at elite boarding school Eton and Oxford University, where he was admitted to the Bullingdon Club, a hard-drinking, socially exclusive student group.

He worked for the Conservatives as an advisor before a stint in public relations, which ended when he was elected to parliament in 2001.

Cameron rose swiftly through the ranks of the party -- which was then struggling badly against then prime minister Tony Blair's Labour government -- and was elected leader in 2005 at the age of 39.

He tried to "detoxify" the party brand in part by avoiding discussion of the EU, which has split the Conservatives since Margaret Thatcher's premiership in the 1980s.

At the 2010 general election, Cameron became the youngest premier for 200 years but the centre-right Conservatives did not win enough seats to govern alone and had to form a coalition with the centrist Liberal Democrats.

The coalition was dominated by spending cuts as Britain emerged from recession, while foreign policy debate was largely hijacked by Conservative wrangling over the EU.

A previous risky referendum gamble paid off when Scotland voted to stay as part of Britain in 2014.

After five years in coalition, the Conservatives won a surprise clear majority in the May 2015 general election, allowing them to rule alone.

The win meant that the EU referendum -- first promised by Cameron in 2013 to placate his restive party, but which many in Westminster say he never believed would happen -- became a reality.

Loyal lieutenants lost

Cameron spent much of the rest of 2015 lobbying other European countries for a deal to improve Britain's relations with the EU.

Sealed in February, this allowed him to argue going into the referendum that Britain had a "special status" in the 28-country bloc, notably allowing it to limit benefit payments to EU migrants.

But the deal was derided as "thin gruel" by some Conservative MPs.

The bitterest blows to Cameron came as campaigning got under way.

Some of his most loyal lieutenants including justice minister Michael Gove -- godfather to one of Cameron's children -- said they would campaign for Brexit.

Then Boris Johnson, who was London's charismatic mayor at the time, sprung a surprise by also backing "Leave".

During the campaign, Cameron led from the front with a barrage of speeches arguing that Britain's economy would be badly hit by Brexit.