Dahlstrom, 21, played in five games during the past two seasons for the Hawks' AHL affiliate, the Rockford IceHogs. He spent the rest of his time playing for Linkopings HC of the Swedish Hockey League. He's coming off his third season, where he tallied a goal and eight points in 50 games.
Dahlstrom was selected with the 51st overall pick in the second round of the 2013 NHL Draft.
The Hawks have signed two other 21-year-old prospects from its 2013 draft class in the last month with Robin Norell and Tyler Motte. Dahlstrom joins Norell, Motte and Ryan Hartman as 2013 signees.
Norell has spent the past two seasons playing for Djurgårdens of SHL. He recorded two goals and six assists in 51 SHL games this season. During his debut season with Djurgårdens in 2014-15, Norell had three goals and six assists in 48 games.
Motte, who is 5'9 and 193 pounds, finished his junior season with 32 goals and 24 assists in 38 games. He was third in the nation in points, only to his two linemates (Kyle Connor and JT Compher), and second in goals to Connor when his season ended March 26 in the regional final of the NCAA Tournament. The left winger was a top-10 finalist for the Hobey Baker Award, given annually to the nation's top college hockey player.