Truss, 47, has been foreign secretary and was the clear front-runner. She clinched victory by appealing to the right-wing party faithful as a tax-cutting, anti-"woke" candidate who would take a hard line on post-Brexit dealings with the European Union.
She inherits a country facing a dire winter energy crisis, widespread strikes and economic recession — as well as long-term questions about the erosion of its cherished public services and its status as a world power after Brexit. Those issues were largely absent from discussion in the two-month leadership race, in which she defeated the former chancellor of the exchequer, or finance minister, Rishi Sunak, by 57% to 43% in the final runoff.
That is a smaller margin than opinion polling had suggested and than her supporters may have hoped for.
As leader of the country's largest party, she will be appointed prime minister by Queen Elizabeth II at Balmoral Castle in Scotland on Tuesday, a break from tradition for the aging monarch, who has always performed the royal duty in London.
Truss, addressing a crowd of Conservative activists and lawmakers at an announcement event in the capital, joked that the lengthy leadership race was "one of the longest job interviews in history."
Her victory means she will become the country’s third female leader, after Margaret Thatcher and Theresa May.
Johnson announced his resignation in July when six months of rolling scandals culminated in a critical mass of his own lawmakers’ abandoning him.
Most of Britain’s 67 million people had no say in Truss’ ascension. Instead, she was chosen by the party’s 180,000 members, who are 97% white; skew older, wealthy and male; and lean to the right of Britain’s political spectrum. Truss does not appear to be hugely popular in polls of the broader public, and she was not the top choice of her party’s lawmakers, but she was the favorite of its members.
The next general election might not be until early 2025; polls give the opposition Labour Party large leads over the Conservatives following the acrimony around Johnson’s fall.
Labour leader Keir Starmer congratulated Truss in a recorded video but added, “The change we need in Britain is not a change at the top of the Tory party,” referring to the Conservative Party by its centuries-old nickname.
Top of Truss’ priorities will be the country’s cost-of-living crisis: skyrocketing bills for food and energy (household electricity and gas bills are set to triple), fears of blackouts this winter and inflation that has sent real-terms wages falling. Millions of people may face the choice between heating their homes or feeding their families, while many small businesses say they will fold unless the government takes action.
Truss has promised to announce her plans on the issue this week. In her acceptance speech, she vowed tax cuts and said: "I will deliver on the energy crisis."
But tackling the crisis is doubly hard because her party is bitterly divided over what to do about it.
Johnson assembled a broad coalition that agreed on one issue — Brexit — said Anand Menon, the director of the U.K. in a Changing Europe think tank. That big tent covers lifelong middle-class Tories in the southern countryside, who may want a small state and lower taxes, to party newcomers from the traditionally Labour-voting north, who generally favor more investment in public services.
“The party is so divided on the only issue that matters to people now, and that’s going to be problematic,” Menon said. “The only issue that matters is the economy.”
Trying to unite those factions is Truss, a political chameleon who, supporters say, has been nimble and pragmatic enough to adapt her views and whom critics decry as opportunistic.
She was born in Oxford to a math professor father and a nurse mother whom she described as “left-wing.” As a student at Oxford University, she supported the centrist Liberal Democrats and advocated such positions as abolishing the monarchy and banning nuclear weapons.
After she switched to the Conservatives, she was elected to Parliament in 2010 following several unsuccessful attempts.
In 2016, she voted to remain in the E.U. in the Brexit referendum. That put her on the liberal — and losing — side of a political and cultural war that has raged ever since. However, she has since switched sides, often displaying the zeal of the convert that seems to have convinced the party faithful.
"She’s loyal, she’s honest, and I’m sure she’ll deliver what she said she would deliver, and I trust her 100%,” said Andrea Andino, 52, sporting an "In Liz we Truss" T-shirt outside the central London conference center where the result was announced.
Tim Bale, a politics professor at Queen Mary University of London, said Truss “wooed” the Conservative grassroots “by telling them what they want to hear — and pretty much only what they want to hear.”
She has tried to burnish those right-wing credentials further by imitating the divisive Thatcher, wearing similar outfits and posing for a photo op in a tank.
Few, if any, pundits regard Truss as a polished orator, and she has become known among critics as overly rehearsed but prone to gaffes. Yet she emerged as the favorite and natural heir to succeed Johnson — still beloved by many on the right even if they accepted it was time for him to go.
In her speech Monday, she paid tribute to Johnson as “my friend."
Johnson quickly repaid the compliment on Twitter, saying Truss "has the right plan to tackle the cost of living crisis, unite our party and continue the great work of uniting and levelling up our country."
Truss had stints as minister for the environment, justice and international trade and most recently as foreign minister, giving her an opportunity to polish her no-nonsense image in dealings over Brexit and Russia’s invasion of Ukraine, where Britain has been a key and valued ally of Kyiv’s defensive fight.
That is unlikely to change with Truss at the helm, although her focus will almost certainly be on the domestic crises greeting her elevation to the top job.