But "Prime Minister Johnson" - a man known for his ambition, blond hair, flowery oratory and cursory command of detail - must solve a series of riddles if he is to succeed where May failed. He will be the 14th prime minister of the queen's 67-year reign.
In a statement, she said: "David's record of service at the Scotland Office - first as a minister in the coalition government, then as secretary of state these last four years - has been exemplary".
Johnson wants to scrap the so-called "Irish backstop", an insurance policy written into the Brexit withdrawal deal to maintain an open border for economic and security reasons between Ireland and Northern Ireland, a constituent of the United Kingdom, until a new British-EU trade deal is reached.
There was a brief hiccup in the smooth handover when environmental protesters blocked Johnson's auto by forming a human chain across the road outside the palace.
Johnson led the 2016 "Leave" campaign and - after May delayed Brexit twice - insists the latest deadline must be kept, calling it a "pivotal moment" in Britain's history.
The Prime Minister has left Downing Street, and is now heading to formally hand in her resignation to the Queen.
Now the real battle starts.
Johnson has vowed that Britain will leave the European Union on the now scheduled date of October 31, with or without a deal on departure terms.
However, Brussels says it will not renegotiate the divorce deal it struck with May to end the 46-year partnership - even though MPs rejected it three times.
"A no-deal Brexit will never be, never, the choice of the EU". We want to keep our journalism open and accessible and be able to keep providing you with news and analysis from the frontlines of Israel, the Middle East and the Jewish World.
Johnson also made various pro-enterprise promises. He also must win over the many Britons opposed to Brexit and resistant to his blustering charms.
As Johnson arrived in Downing Street from Buckingham Palace to take up the reins of power, Symonds was front and centre among dozens of staff and aides cheering his arrival from further down the road.
Mr Johnson has repeatedly pledged to "take back control of our fishing waters" by leaving the European Union on October 31, with or without a deal. "Like some slumbering giant, we're going to rise and ping off the guy-ropes of doubt and negativity", Johnson told his supporters.
He has previously refused to rule out voting against his own government on the backbenches to stop a no-deal outcome, and has warned it could leave a £90bn dent in the public finances.
He joins the Chancellor of the Exchequer Philip Hammond, global development secretary Rory Stewart and justice minister David Gauke in resigning from the cabinet.
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Anyone with information is asked to contact the Northern Rockies RCMP at 250-774-2700 or Crime Stoppers at 1-800-222-8477. Four days after Fowler and Deese were found dead , emergency services went to a vehicle fire 50 km south of Dease Lake.
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