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 75^th anniversary of D-Day, and the G20).