Lassgård was born in Östersund, Jämtland. A keen amateur ice hockey player in his youth, he also joined theatre teacher Ingemar Lind's Institute for the Performing Arts in the village of Storhögen outside Östersund. He then attended the Stage School in Malmö from 1975 to 1978. There Lassgård met the director Peter Oskarson and joined his Skånska Teatern theatre company at Landskrona, where he remained for four years, making his first television appearance as "Puck" in its production of A Midsummer Night's Dream in 1980. Lassgård followed Oskarson to the Folkteatern company in Gävle in 1982, giving a series of highly acclaimed performances.[1]