Financial terms were not released. The 17-year-old defenseman was the No. 8 pick in the 2018 NHL Draft.
Boqvist had 24 points (14 goals, 10 assists) in 25 games with Brynas in the SuperElit League, one assist in 15 games with Brynas IF of the Swedish Hockey League, and two assists in seven games with Almtuna IS in the Allsvenskan League last season.
"We're looking to kind of play a role in his development over the next couple years," Blackhawks general manager Stan Bowman said. "The goal is to get him ready for the NHL as soon as possible. We don't really have a timetable on that. It was just recently we were able to get him in our organization, and we had discussions last week about probably the right thing to do is to get him signed.
"We love the potential and the skill set that he has, and now it's a matter of taking that to the next level."
Boqvist (6-foot, 165 pounds) had six points (three goals, three assists) in six games to help Sweden win the bronze medal at the 2018 IIHF Under-18 World Championship and was named the best defenseman of the tournament. He helped Sweden to the bronze medal at the 2017 Ivan Hlinka Memorial Cup, ranking second with eight points (one goal, seven assists) in five games.
"Obviously, he's got a ton of talent," Bowman said. "We're really excited about his skill set, what he brings to the table. He's a dynamic offensive defenseman."
