The midfielder – who spent last season on loan at the New York Stadium – has signed a three-year deal with the Championship club.
Barlaser, 23, was set to miss out on a place in Newcastle United’s 25-man Premier League squad – and Steve Bruce opted to sell him for an undisclosed fee so he could play first-team football.
"I wish Dan the very, very best of luck," said United’s head coach. "He had a wonderful loan spell last year. He's got to an age where I think he needs to play, and I hope he goes and has a wonderful career. He's been with us since he was nine years old, and I wish him the best of luck."
Newcastle United to ‘push ahead’ with £48m double raid, Toon in ‘pole position’ for £42m Tottenham star
Tottenham Hotspur star ‘banished’ from squad amid Newcastle United speculation - reports
Newcastle United ‘in talks’ over Chelsea duo, Toon set to walk away from ‘£60m’ discussions
Newcastle United 'closing in' on £13m striker following St James's Park visit
What Eddie Howe has said on Newcastle United transfers as club prepare €30m Goncalo Ramos bid
Meanwhile, Newcastle striker Elias Sorensen, 21, has joined Almere City on a season-long loan. The club competes in Holland’s second division.