Hans Mosesson was born in the Enskede district of Stockholm. He studied medicine at the University of Lund in the 1970s. In Lund, he met the newly founded leftist theatre and musical group Nationalteatern, and Mosesson quit his studies and joined the group and moved with them to Gothenburg. He was featured in many Swedish films and TV-productions. And during the 2000s he was a household face in Sweden as he starred as the grocer Stig in the first 512 episodes of the long-running weekly advert series for the grocery chain ICA from 2001 to January 2015.