Theresa May

Conservative Party

Image credit: Theresa May, Andrew Parsons/i-images, 1 August 2016. FOI Team Mailbox, Prime Minister’s Office. Open Government Licence v3.0

Theresa May

And I know because we’re Great Britain, that we will rise to the challenge. As we leave the European Union, we will forge a bold, new positive role for ourselves in the world, and we will make Britain a country that works not for a privileged few, but for every one of us.

Conservative Party

July 2016 - July 2019

13 Jul 2016 - 24 Jul 2019

Theresa May, 1 August 2016

Image credit: Theresa May, Andrew Parsons/i-images, 1 August 2016. FOI Team Mailbox, Prime Minister’s Office. Open Government Licence v3.0

Key Facts

Tenure dates

13 Jul 2016 - 24 Jul 2019

Length of tenure

3 years, 11 days


Conservative Party


Sir Philip May


1 Oct 1956

Birth place

Eastbourne, England

About Theresa May

Theresa May was the unexpected successor to David Cameron. She initially planned a government that would focus on delivering the Brexit mandate and social reform. But, the 2017 election damaged her authority, and the rest of her ministry was largely concerned with a fraught attempt to negotiate a Brexit deal acceptable to the fractious Conservative Party.

Theresa May was born Theresa Mary Brasier in 1956. She was the daughter of an Anglican minister. She grew up in rural Oxfordshire. She attended Holton Park Girls’ Grammar School and St Hugh’s College, Oxford. She worked in banking during the 1980s and 1990s, and was elected to Parliament in 1997. She served in successive Shadow Cabinets, before being appointed Home Secretary by David Cameron in 2010. She became the longest serving Home Secretary since the 1950s.

After Cameron’s resignation, most expected Boris Johnson to win the party leadership election, but his campaign suddenly collapsed, leaving May the frontrunner. After rival Andrea Leadsom withdrew, May suddenly became leader and Prime Minister in July 2016.

She quickly worked to establish her credentials, triggering Article 50 in March 2017, putting a two-year time limit on Britain’s negotiations. By April 2017, May was popular, and she sought to take advantage of that popularity by calling an election.

The polls predicted a heavy Conservative majority, but May’s campaign soon stalled, and she was revealed to be a much weaker campaigner than her opponent. The election finished in a hung Parliament, with a rapidly organised ‘confidence and supply agreement’ with the DUP ensuring that the Conservatives remained in office.

The rest of May’s time in power would be dominated by controversy over Brexit negotiations with Europe and Conservative Party factionalism. She succeeded in negotiating a withdrawal agreement, but it was repeatedly rejected by the Commons. On 24 May 2019, with her support within the Conservative Party no longer guaranteed, she announced her resignation.

Key Events


Theresa May was the unexpected inheritor of the premiership in July 2016. Neither Cameron’s resignation, not Boris Johnson’s withdrawal from the campaign, were anticipated. When she became Prime Minister, her speech focused not on Brexit, but on building ‘a country that works for everyone’.

Prime Minister Theresa May smiling during an official meeting with the President of Ukraine
LONDON, UK – Apr 10, 2017: Prime Minister of the United Kingdom Theresa May smiling during an official meeting with the President of Ukraine Petro Poroshenko at 10 Downing Street in London. Photo by palinchak/

She expelled many of Cameron’s appointments, replacing Chancellor George Osborne with Philip Hammond and promoting Amber Rudd as the new Home Secretary. More generally, this was interpreted as shifting the government to a more right-wing basis than the previous one.

In the early months of her premiership, she visited other foreign leaders, including to the European Council to begin Brexit negotiations. She was the first foreign leader to meet US President Donald Trump after his inauguration on 27 January.

On 29 March 2017, May triggered Article 50. This began a two-year countdown on Brexit. That day, she told the Commons:

“This is an historic moment from which there can be no turning back. Britain is leaving the European Union. We are going to make our own decisions and our own laws. We are going to take control of the things that matter most to us. And we are going to take this opportunity to build a stronger, fairer Britain – a country that our children and grandchildren are proud to call home.”

Parliament endorsed the decision by 498-114. But, in retrospect, the invocation of Article 50 without an agreement, gave the EU a great deal of leverage for the negotiations that followed.

On 18 April 2017, May gave a surprise speech outside Number 10. She announced that she favoured a general election on 8 June. She cited the efforts of opponents to thwart Brexit and said: “Division in Westminster will risk our ability to make a success of Brexit and it will cause damaging uncertainty and instability to the country.” Parliament gave its assent, and the 2017 election campaign began.

But, the campaign did not prove to be the easy victory that May had expected. She earned the nickname ‘Maybot’ from her rote responses to questions. She made policy mistakes, which were pounced upon by the opposition. Her opponent, Jeremy Corbyn proved a much more effective campaigner than many had anticipated. When the results came late on the evening of 8 June, May had lost her majority. A ‘confidence and supply’ agreement was reached with the Northern Irish Democratic Unionist Party, which kept the Conservatives in government, but May was left terribly weakened politically. To compound matters, her two most trusted advisers, Nick Timothy and Fiona Hill were forced to resign.

The situation was worsened by May’s apparently unfeeling response to a terrible fire at the Grenfell Tower in London that killed 72 people.

May would be more decisive after a series of Islamic extremist terrorist attacks in May and June 2017. After a suspected Russian poisoning attack on a defector in March 2018, as a consequence of which a British civilian died, May shaped the western response. Sanctions were introduced on Russia, and over 150 Russian diplomats were expelled from western countries.

For the next two years, May’s government focused on securing a Brexit deal, through difficult and tortuous negotiations with the European Union. On 6 July 2018, she set out her negotiating plan to her cabinet at Chequers. It proved too much for senior ministers David Davis and Boris Johnson, who resigned in protest.

May brought back an agreement in November 2018. But the Conservative Party was bitterly divided. In December 2018 she faced down a party vote of no-confidence by Brexiteer Conservatives and defeated a Parliamentary vote of no confidence the following month. Her agreement was rejected three times by the Commons.

By the spring of 2019, it was becoming clear that the Conservative Party no longer had confidence in her leadership. After a last-ditch attempt to negotiate with the Labour Party in 2019, May realised there was no longer any way to remain in power, and she resigned in May.

“I feel as certain today as I did three years ago that in a democracy, if you give people a choice you have a duty to implement what they decide. I have done my best to do that. I negotiated the terms of our exit and a new relationship with our closest neighbours that protects jobs, our security and our Union. I have done everything I can to convince MPs to back that deal. Sadly, I have not been able to do so.”

May was relatively fortunate that her premiership continued for another month, allowing her to attend a number of diplomatic events (including Donald Trump’s state visit, the 75th anniversary of D-Day, and the G20).

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