The Scarborough-born Conservative, who had previously been the Chief Whip in Theresa May's government, was promoted to the role this morning.
Originally from Scarborough, he was educated at East Ayton Primary School and Scarborough Sixth Form College, before getting his degree at the University of Bradford. He has been MP for South Staffordshire since 2010.
Last night, Sir Michael Fallon became the first ministerial head to roll in the Westminster sleaze scandal.
He quit after admitting his behaviour had "fallen below the high standards required" in the role and acknowledging that what might have been acceptable in the past was no longer appropriate.
Mr Williamson, who was made a CBE by outgoing Prime Minister David Cameron, helped to run the leadership campaign of Theresa May and was at the forefront of the agreement with the DUP to ensure itNorthern Ireland MPs boosted her Parliamentary majority.
Profile,a Radio 4 spotlight by broadcaster Mark Coles, described him as being "brutally efficient behind the smiles and will do whatever it takes" to achieve objectives. He began his political rise as president of the Conservatives students at Bradford University, although his parents are said to have been Labour supporters.
He later ran a Staffordshire pottery firm selling tableware and was said by the programme's interviewees to have "boundless energy and optimism".
As an MP, he was selected for the high-rank role as Parliamentary Private Secretary to Mr Cameron and leaped "to the centre of the party – dealing with everyone in the Commons". His appointment as chief whip gave him a massive promotion, the Profile programme said. He was described as a networker, playing a "pivotal role" in gaining a majority for Mrs May in the Commons by liaising face-to-face with the DUP in Belfast.
The father-of-two has many other interests – including a pet tarantula called Cronus which he has taken to the Commons.