LONDON — Her beloved father, an Anglican vicar, died in a car crash when she was 25, after she had been married only a year, and her mother, who had multiple sclerosis, died a few months later. For Theresa May, a cherished only child, the shock was devastating.
It brought her even closer to her husband, Philip, two years younger, whom she had met at Oxford, at a Conservative Party disco. They bonded over cricket and silly university debates, like the one where Philip induced her to speak for the motion “That sex is good… but success is better.”
Both became bankers, and Ms. May threw herself into the Conservative politics that had entranced her since the age of 12, when she liked to argue with her father and he asked her, in order to maintain neutrality in his parish, not to parade her Tory colors in public.
“Politics captured me,” Ms. May said in 2014. “That sounds terribly trite,” she said, but “I wanted to make a difference, I wanted to be part of the debate.”
On Wednesday, Ms. May, 59, became Britain’s prime minister, the last adult standing after other senior members of her party — the clever younger men from Britain’s elite schools, like her predecessor, David Cameron — schemed each other out of contention.
For Ms. May, only Britain’s second female prime minister, it is a job she never publicly acknowledged wanting, until Mr. Cameron, bluff and self-confident, pushed his luck once too often, lost the referendum on keeping Britain in the European Union and quit.
Ms. May, who had been home secretary, is considered “a safe pair of hands,” not flashy and even dull, who seems to be a candidate of continuity. But the country’s dire circumstances may demand more. And Ms. May, a traditional economic and social conservative in many respects, has signaled a desire to give her party a new focus on the need to build a fairer society.
With Britain deeply divided over its decision to leave the European Union, its place in the world in flux, its unity threatened by calls for Scottish independence and its economy at risk, the times may require that Ms. May be both steady and bold.
Her six-year tenure at the Home Office showed her to be a tough operator and put her in charge of a number of flash-point issues. She demanded police reforms to reduce racial profiling. She helped push through surveillance policies that had to balance fears of terrorism against civil liberties and confronted public pressure to reduce immigration, failing to meet government targets for doing so. If sometimes at odds with Mr. Cameron’s inner circle — she was a quiet critic of the government’s budget austerity — she nonetheless built a reputation as smart and competent.
Damian Green, who worked for her as Home Office minister until 2014, said that “Theresa doesn’t do verbiage, doesn’t do speeches for the sake of making speeches. One of her virtues is that when she says something today she means it tomorrow.”
But she will have to bind a badly torn party in which she has won esteem but few close friends. She will also have to juggle competing priorities in negotiating the withdrawal from the European Union under the watchful eye of Brexit supporters who remain wary of her commitment to their cause.
Even though she publicly if tepidly supported remaining in Europe out of loyalty to Mr. Cameron, saying it would be best for the nation’s security, at heart “she is a Euroskeptic,” said Catherine Meyer, a former treasurer of the Conservative Party and a friend of the Mays’. “When she says Brexit means out, she means it.”
While respected within the European Union as a tough and unpretentious negotiator, Ms. May will have to find the right balance between more controls on immigration that the voters demanded and at least partial access, if she can manage it, to the single market of the European Union.
Friends say that her early religious upbringing — she is an Anglican but went to a Roman Catholic school — has given Ms. May a moral base, a steady personality and a feeling for the disadvantaged. “Her background has shaped her into somebody who is not going to feel sorry for herself or blame others for her mistakes, and who finds solace in moving forward, not to sit but to fight,” said Ms. Meyer, who worked with Ms. May on a charity for abducted children.
A young woman who hunched her shoulders at school to seem less tall has grown into a proud master of her responsibilities. She lives for her work and her husband, a well-off investment banker, and their time together in their neat house in Sonning-on-Thames, in Berkshire, in the heart of her Maidenhead constituency, a village she shares with better-known types like the guitarist Jimmy Page and George and Amal Clooney. She likes to cook and owns more than 100 cookbooks, and will likely be glad that the Camerons took the heat for remodeling the ancient kitchen at 10 Downing Street.
Mr. Cameron valued her workaholic talents, naming her Home Office secretary, one of the four senior cabinet posts, only the second woman to hold the job. Wary of her quiet ambition and wanting to protect his own favorite, George Osborne, the chancellor of the Exchequer, he never promoted her further. But he did not demote her, either, even as she failed to deliver on one of the government’s key pledges, to curb immigration. She was famous for fighting her corner, knowing her subject and keeping clear of the Cameron “chumocracy.”
Ms. May is polite but not chummy, works late and does not hang around Parliament’s bars. Her lack of a “set of friends” was considered one of her great liabilities in the race to succeed Mr. Cameron, said Crispin Blunt, a Conservative member of Parliament who is one of her supporters. “There wasn’t an army of mates for her,” he said, but it allows her now to make appointments to her government on the basis of her own priorities and assessments.
“In government, sometimes it’s difficult to be a woman surrounded by lots of men,” said Ms. Meyer. “Like Margaret Thatcher, she likes the company of men, but she’s capable of putting her fist down.”