Eales joins from US Major League Soccer (MLS) club Atlanta United, where he has been President and Chief Executive since the team was founded in 2014. Over that time, he has built a franchise that has secured the highest average attendance in MLS, created the most valuable squad, generated the largest profits - and won multiple trophies, including the MLS Cup in 2018, the US Open Cup in 2019 and the Campeones Cup in 2019.
The 49-year-old will work alongside the Magpies' sporting director, Dan Ashworth, for the second time in his career after the two worked closely at West Bromwich Albion between 2006 and 2010.
Born in Chelmsford, Eales attended Ivy League establishment Brown University in the United States, graduating with a first-class degree in economics and being named the Ivy League Football Player of the Year in 1994 while playing in the US college system.
He subsequently read law at Cambridge University back in the UK before becoming a member of the bar in 2000 and practised at 2 Temple Gardens Chambers, where he remains a door tenant.
In 2006, he joined West Bromwich Albion, serving as Legal Director and Club Secretary, before leaving to become Director of Football Administration at Tottenham Hotspur in 2010.
In 2014, Eales became president of the newly-awarded franchise Atlanta United FC, and led the club through its inaugural season in 2017 to then become MLS Cup winners in 2018 - with a side including Miguel Almirón.
Assembling the club's front office, developing its brand identity and integral to the appointment of several of the franchise's technical team, Eales was also central to Atlanta United's move into the impressive Mercedes-Benz Stadium in 2017, where the club has consistently ranked in the top 15 globally for football attendance.
Eales has a stellar reputation and he has been named the MLS Executive of the Year on two occasions. He was also named World Football Summit Executive of the Year in 2019.
Eales said: "Newcastle United is both a giant of a club, and the heartbeat of its community. Every time I have visited St. James' Park, I've been overwhelmed by the passion of the fans.
"This is a club with an amazingly rich heritage, and I am delighted to be joining for this new chapter in its long history.
"I am grateful for the opportunity, and look forward to working with the rest of the team to help this storied club fulfil its potential."
The club's investment group, comprising PIF, PCP Capital Partners and RB Sports & Media, said: "We are delighted to announce Darren Eales as the club's new CEO. He is an exceptional leader and is a great fit for Newcastle United.
"We have conducted an exhaustive recruitment process to ensure we identified and secured the right individual for the CEO position, and we are confident we have found that person in Darren.
"He has a deep understanding of the football industry and what it takes to achieve growth and success, and he will be a key member of the club's leadership team as we look to deliver on the club's potential on and off the pitch."
