The Labour MP acknowledged that seeking to combine the job with his role at Westminster had raised eyebrows, but insisted he could not “stand on the sidelines” while the future of the region was being decided.
Voters across Sheffield, Rotherham, Barnsley and Doncaster elected Mr Jarvis to serve as the region’s first ‘metro mayor’.
But the powers available to Mr Jarvis are far from being agreed with Government and the devolution process has been dogged by deep divisions.
Barnsley Central MP Mr Jarvis took 48 per cent of the vote in the first count and was elected mayor after the second count, which saw him comfortably defeat his Tory rival Ian Walker.
In his victory speech he stressed the case for a wider Yorkshire devolution deal and defended his decision to stand in the election. “I understood then that the exceptional nature of my candidacy would raise some eyebrows and it has,” he said.
“But I believed then, as I know now, that the exceptional circumstances of this mayoralty and the importance of devolution for the future of the UK meant that I couldn’t stand on the sidelines and that I had to step forward.
“I say this because I believe that the issue of devolution goes to the heart of two of the most important strategic issues that our country faces - how we respond to the causes of Brexit and how we prepare for a post-Brexit Britain.
“If we are to find the right answer to these questions we must be prepared to reform every aspect of our political system.”
The election has been mired in the wider controversy surrounding devolution in Yorkshire which has led to a split within the South Yorkshire local authorities.
Doncaster and Barnsley have joined with 16 other local authorities to back a plea to the Government to deliver a pan-Yorkshire devolution deal.
Sheffield and Rotherham, which favour a South Yorkshire deal, were the only Yorkshire councils not to sign up to this proposal earlier this year.
A South Yorkshire region devolution plan was agreed with Government in 2015 but ran into a range of problems.
Mr Jarvis, who echoed the late Labour MP Jo Cox’s comment that people had “more in common” with each other than things which divided them, called for Yorkshire to pull together to address the challenges it faces.
“Today is not the end of Yorkshire’s devolution story, it is only the beginning,” he said.
Mr Jarvis, a former Parachute Regiment officer, has been a vocal supporter of attempts to secure a pan-Yorkshire devo deal.
In his mayoral manifesto he said: “I believe that a fully established wider Yorkshire deal - which encompasses the 5.4 million people who live in our region - is the right way to prepare for life after Brexit.”
Mr Jarvis’s victory was immediately hailed by the influential Confederation of British Industry, who urged him to make increasing productivity the cornerstone of his economic vision in the coming months.
It said its analysis showed that if Yorkshire and Humber’s productivity grew at the same pace as the region’s best performing area did between 2004 and 2014, the gain to its economy could be £13.5 billion by 2024. Beckie Hart, Yorkshire and Humber Director for the CBI, said: “The new mayor will have responsibility for growing the region’s economy at a critical time for both Sheffield City Region and the UK as a whole.
“Working in partnership with businesses of all sizes and sectors from across the area will help establish priorities for raising productivity, such as improvements in infrastructure and education.
“This matters as increasing productivity is the only sustainable route to higher wages, and therefore living standards.
“We look forward to working closely with Dan Jarvis as he develops his economic vision in the coming months to help unlock more jobs, investment and prosperity for the region as a whole.”