When Did Theresa May Become Prime Minister
Theresa May became Prime Minister of the United Kingdom on 13 July 2016, following the resignation of David Cameron after the Brexit referendum. She was the second female Prime Minister in UK history and took office as leader of the Conservative Party after winning the internal leadership contest without a public general election ballot. Her appointment marked a clear transition in UK executive leadership at a time of heightened uncertainty over Brexit negotiations.
Before becoming Prime Minister, Theresa May served as Home Secretary from 2010 to 2016, making her the longest-serving Home Secretary in over 60 years. She built a reputation for a focused, technocratic style of governance, emphasizing law and order, immigration controls, and national security. Her rise to the premiership reflected support from senior Conservative Party figures who prioritized stability and experienced executive management during a period of political and economic change.
Key Dates and Political Context
The key date for Theresa May becoming Prime Minister is 13 July 2016, the day she officially accepted the invitation to form a government from Queen Elizabeth II. The date followed the formal conclusion of the Conservative leadership election, in which she defeated Andrea Leadsom to become party leader. The transition happened within the constitutional framework of the UK, where the monarch invites the leader of the majority party in the House of Commons to form a government.
The political context centered on the United Kingdom's vote to leave the European Union in the 2016 referendum. May entered office with a mandate to deliver Brexit while maintaining unity within her party and the country. Her early government included a cabinet reshuffle that placed strong Brexit advocates in key roles, signaling that executing the referendum result would be the central priority of her administration.
Premiership and Leadership Timeline
Major Policy and Governance Actions
During her premiership, Theresa May triggered Article 50 of the Treaty of Lisbon on 29 March 2017, formally starting the UK's withdrawal process from the European Union. She called a snap general election in June 2017, which resulted in a hung parliament and forced her to rely on support from the Democratic Unionist Party to maintain a working majority in the House of Commons. Her government pursued a controversial Withdrawal Agreement that faced multiple defeats in Parliament, contributing to political instability.
May's leadership was defined by repeated parliamentary clashes over her Brexit deal, which she negotiated with EU leaders including European Commission President Jean-Claude Juncker. She survived a confidence vote within the Conservative Party in December 2018 but ultimately announced her resignation as party leader on 24 May 2019, remaining as caretaker Prime Minister until Boris Johnson succeeded her. Her tenure is widely referenced in analyses of UK executive decision-making and is documented in detailed timelines on authoritative government and historical resources.
Succession and Legacy
Boris Johnson formally replaced Theresa May as Prime Minister on 24 July 2019, after winning the Conservative Party leadership election. May's legacy includes the operational execution of the UK's departure from the European Union, which was completed on 31 January 2020, under the terms she had negotiated. Her premiership is frequently cited in studies of crisis leadership and constitutional conventions, and her career trajectory is covered by major financial and political news outlets.
Further Reading
For additional context on UK executive transitions and political risk, see the detailed timeline on the official UK Parliament website and expert commentary on governance and policy shifts available through Reuters.