Nick Clegg becomes Britain's first Deputy Prime Minister since John Prescott stepped down in 2007, and the first Liberal one for decades. It's not necessary that Britain has a Deputy Pm. He'll just run the country whenever David Cameron is abroad attending summits or meeting PMs and Presidents, and he'll do so later this year when Cameron takes paternity leave. But he still has the job of leader of the Liberal Democrats.
This is the first coalition government to come into power in Britain since 1940. That's as a result of Britain's first hung parliament - in which no party gets an outright majority - since 1974.
Back then, the Conservative government, led by Prime Minister Edward Heath, won a larger share of the votes (but only just) than Harold Wilson's Labour Party (37.9% to 37.2%) but Labour won more seats in the Commons than the Tories (301 to 297). The Liberals (once known as the Whigs), led by Jeremy Thorpe won 19.3% of the vote and 14 seats.
So the Tory government tried to form a coalition government with the Liberals. However, Thorpe was never enthusiastic about supporting the Conservatives, and demanded major electoral reforms in exchange for such an agreement (just as they have done in forging an agreement with the Tories this time).
Unwilling to accept such terms, Heath resigned and Wilson returned for his second spell as
Prime Minister. However, Wilson only lasted until 1976 and then James Callaghan took over as PM. His disastrous reign oversaw strikes and the 1978/79 Winter of Discontent. Needless to say, he was soundly beaten by Margaret Thatcher in the 1979 election, who went on to serve 11 years as PM, winning three General Election.
However, the 2010 election wasn't as close, with the Tories gaining two million more voted than Labour and 50 more seats than Labour. It seems as though the British people wanted a Tory Government but a hung parliament came along entirely accidentally. During the campaign, Lid Dem leader Nick Clegg thought it would be democratic if he first tried to help the party which won most seats and most votes to form a government, which was the Tories. They did speak to the Labour Party during the five days of negotiations but apparently Labour weren't that interested, knowing that it'll be much more difficult for them to form an alliance.
What we are seeing now is very strange times in British politics, with a coalition ruling over us for the first time since WWII. However, Churchill's coalition had no Liberal Party MPs in it, so this is the first time that Britain has been ruled by the Liberals since 1922.
David Cameron has also become the youngest British Prime Minister since Lord Liverpool in 1812. He's six months younger than what even Blair was when he came to power in 1997.
And we've got minor royalty in Downing Street. Cameron is the direct descendant of the eccentric King William IV (Queen Victoria's uncle) and his wife Samantha is a direct descendant of "merrie monarch" King Charles II and his mistress, the actress and orange seller Nell Gwyn.
And I bet that Liberal leader Nick Clegg didn't think that after this year's General Election that we would become Deputy Prime Minister. Anyone who thought that would have been locked up in Broadmoor.
Today Britain's two new leaders held a press conference in 10 Downing Street's beautiful garden. Though it was strange to see the men acting like good buddies when they used slag each other off in the Commons every week and also during the three televised Leaders' Debates during the campaign. A couple of years ago, Cameron was asked what his favourite joke was. He replied: "Nick Clegg."
New deal: Prime Minister David Cameron (right) and Deputy Prime MinisterNick Clegg in the Downing Street garden today on their first day in office
Partnership: The new Prime Minister and his deputy stroll across the lawn towards the waiting media