Rishi Sunak on Tuesday made history after becoming Britain's first Indian-origin Prime Minister. He was elected unopposed as the new leader of the governing Conservative Party on Monday, following Penny Mordaunt's withdrawal from the race.

Following is the chronology of the main events illustrating Sunak's second shot at the UK Prime Minister's post.

2015: Rishi Sunak was elected the Conservative MP for Richmond, Yorkshire.

2016: Sunak is a lifelong Brexiter, and accordingly campaigned for leave, a gamble at the time but one that paid off as it put him in good political stead within the Tory party in the years to come.

2018: Under Theresa May, Sunak is given his first ministerial job as number three at the newly renamed Ministry of Housing, Communities and Local Government.

July 2019: Sunak endorses Boris Johnson for British Prime Minister and is rewarded by the new leader with a job as Treasury minister under then Chancellor Sajid Javid.

February 2020: After Javid resigns over a power battle between No. 10 and No.11 Downing Street, Boris Johnson promotes Sunak to the role of Chancellor making him the first minister of Indian origin to hold one of the highest offices in the British government.

April 2020: After the UK goes into full lockdown in March 2020 as the COVID pandemic takes hold, Sunak wins praise for a series of mini budgets to introduce measures such as the furlough scheme, which goes on to save many jobs and businesses.

2021: Rishi Sunak is pitted as a clear favourite to succeed Boris Johnson as Tory leader as Johnson's party gate troubles begin swirling, though the British Indian Chancellor holds firm that his focus is only on the Cabinet job at hand.

February 2022: UK Chancellor Sunak admits being present at a party for his boss Johnson's birthday in the Cabinet room of Downing Street, in breach of lockdown rules in place back in June 2020.

April 2022: Sunak's wife Akshata Murty's legal non-domicile tax status, meaning she doesn't pay UK taxes on her Infosys income, creates controversy. Sunak's own US Green Card while in office also becomes an issue.

July 2022: Rishi Sunak resigns as Chancellor, just moments after his former boss in the Treasury Sajid Javid as Health Secretary.

July 8: Rishi Sunak launches bid to succeed Boris Johnson as UK PM.

July 20: Rishi Sunak races ahead with 137 votes as the frontrunner with his party colleague, to face off with Liz Truss in the final leg of the British PM contest.

August 5: Rishi Sunak wins over voters in a TV debate.

August 30: Rishi Sunak camp accuses Liz Truss of avoiding scrutiny.

September 1: Rishi Sunak closes the campaign on a personal note with parents, wife Akshata.

September 2: Voting closes in the UK Prime Minister race between Rishi Sunak, and Liz Truss.

September 5: Truss defeats Sunak in the Conservative Party leadership race to become the new British PM.

October 14: UK PM Liz Truss sacks Kwasi Kwarteng as Chancellor amid economic turmoil.

October 19: Truss resigns as British PM after six weeks amid an open revolt.

October 24: Sunak wins Tory contest to make history as UK's first Indian-origin PM.

October 25: Sunak becomes Britain's first Indian-origin Prime Minister after meeting King Charles III.