After having lost his working majority to defections and his own suspensions of rebel Members of Parliament, Johnson called a general election on a platform of completing the UK's withdrawal from the European Union.

In that general election, the Conservative Party won their biggest majority in Parliament since 1987, and Johnson was able to pass a revised version of May's withdrawal agreement.

Truss would later resign after just 50 days in office amid an economic and political crisis, which made her the shortest-serving prime minister in British history.

[6] In the aftermath of the 2016 United Kingdom European Union membership referendum, David Cameron resigned the office of prime minister and was succeeded by Theresa May.

After triggering Article 50, a legal process that started the UK's formal departure from the EU, she called an early general election, aiming to secure a larger Conservative majority to support her proposals for Brexit.

He lost this when the Conservative MP Phillip Lee crossed the floor on 3 September 2019 to join the Liberal Democrats, accusing Johnson's government of "aggressively pursuing a damaging Brexit in unprincipled ways".

[13] Twenty-one Conservative MPs voted to allow the House of Commons to consider a bill tabled by the Labour MP Hilary Benn that would require Johnson to seek an extension to date of the UK's withdrawal from the European Union from 31 October 2019 to 31 January 2020 if Parliament had not approved a withdrawal agreement or voted to allow the UK to leave the EU without a deal.

[15][16] Johnson sought an early general election, but was initially unsuccessful as a majority of MPs wanted to remove the possibility of the UK leaving the EU without a deal.

"[22] A legally-enforced lockdown was announced on 23 March, banning all non-essential travel and contact with other people, and shutting schools, businesses, venues and gathering places.

[25] Johnson's government responded by enacting emergency powers and widespread societal measures including several lockdowns, and approved a vaccination programme that began in December 2020.

[26] While reception for Johnson's leadership during the crisis was mixed, the Conservative Party consistently, if narrowly at times, lead in the polls during the pandemic.

[29] Beginning in December 2021, the media reported that there had been social gatherings by the Conservative Party and UK government staff during public health restrictions due to the COVID-19 pandemic.

[38] Conservative Party rules mean that a confidence vote is triggered by 15% of MPs sending letters to Graham Brady, who chairs the 1922 Committee.

[42] Around the same time, the Conservative MP William Wragg said that his party's whips were using blackmail and threats of withdrawing funding in MPs' constituencies to secure their votes.

[40] Another Conservative MP, Nus Ghani, said that a whip had told her that her practice of Islam was discussed when deciding to fire her from her ministerial role in 2020.

[45] On 3 February 2022, when eight MPs had publicly announced that they had submitted letters of no confidence in Johnson, the Financial Times reported that "backbenchers estimate the actual number to be in the region of 30".

[51] In late June 2022, the Conservative MP Chris Pincher resigned as deputy chief government whip after allegations were made that he had groped two men.

The former permanent secretary to the foreign office Simon McDonald wrote that Johnson had been personally briefed on previous allegations against Pincher in 2019.

[87][88] Suella Braverman, the Attorney General for England and Wales, was the first Conservative MP to publicly declare her candidacy, announcing before Johnson resigned.

[89] During an ITV interview with journalist Robert Peston, she called for Johnson to step down as prime minister but said she would not resign from his cabinet because she had a "duty and we need an Attorney in government".

[93][94] Rehman Chishti, the MP for Gillingham and Rainham, announced he was running on 10 July, saying he offered a "fresh start" and advocating "aspirational conservatism".

[100] He pledged to legalise fox hunting and to maintain the government policy of sending refugees to Rwanda, saying he hoped to expand the programme to other countries.

[107][101] After his resignation, allies of Johnson said that Javid had argued for stronger pandemic restrictions to be applied around Christmas 2021 as well as a policy to require staff at large companies to either be vaccinated or to wear masks and get COVID-19 tests weekly.

[114] The video included footage of Oscar Pistorius, an athlete who was convicted of murder, and the British Paralympian Jonnie Peacock, who requested to be removed.

[120][121] Grant Shapps, the transport secretary, announced his candidacy on 8 July in an article for The Times, emphasising that he had been loyal to Johnson and had not been preparing a leadership campaign "behind his back".

[122] He argued against the "unnecessary continuation" of spending and restrictions introduced due to the COVID-19 pandemic and proposed a policy platform including tax cuts and "state support to firms with high levels of energy consumption".

During the campaign, Sunak pledged to included tax cuts only when inflation was under control, scrapping of the 5% VAT rate on household energy for one year, introducing a temporary £10 fine for patients who fail to attend GP appointments, capping of refugee numbers, and a tightening of the definition of asylum.

[131] Tom Tugendhat, the chair of the Foreign Affairs Select Committee, announced his candidacy in The Daily Telegraph on 7 July, highlighting his previous experience in the British Army.

[145] On 9 July, The Independent reported that HM Revenue and Customs were investigating his tax affairs, after the case had been transferred to them from the National Crime Agency's International Corruption Unit.

[147] Tara John of CNN noted several candidates going to lengths to display their anti-transgender positions, despite polling indicating that it is not a particularly important issue to the British public.