When did Boris Johnson become Prime Minister? A timeline of his time as PM, and how long he was in power
![Boris Johnson pulls out of race to be leader of UK's Conservative Party and next prime minister | CNN Boris Johnson pulls out of race to be leader of UK's Conservative Party and next prime minister | CNN](https://media.cnn.com/api/v1/images/stellar/prod/221023161709-boris-johnson-file-1023.jpg?c=original)
Boris Johnson pulls out of race to be leader of UK's Conservative Party and next prime minister | CNN
![When did Boris Johnson become prime minister and why did Theresa May resign? - Manchester Evening News When did Boris Johnson become prime minister and why did Theresa May resign? - Manchester Evening News](https://i2-prod.manchestereveningnews.co.uk/incoming/article16638816.ece/ALTERNATES/s1200b/0_boris.jpg)
When did Boris Johnson become prime minister and why did Theresa May resign? - Manchester Evening News
![Boris Johnson vows 'I'll be back' as ex-prime minister formally resigns as MP | Politics News | Sky News Boris Johnson vows 'I'll be back' as ex-prime minister formally resigns as MP | Politics News | Sky News](https://e3.365dm.com/23/06/2048x1152/skynews-boris-johnson-partygate_6184611.jpg)