Youngest of 4 children, Jonas Jacobsen grew up as part of the Danish minority in Flensburg, Northern Germany, his father being a minister for the Danish church in the area. His Swedish mother was mainly at home taking care of the children. After a year as an exchange student in Australia, his appetite to see the world grew. After high school he went on several trips around the world, gaining knowledge about cultures and languages until moving to Copenhagen, where he started acting in the underground theatre scene. After a brief detour at the Royal Academy of Architecture in Copenhagen, he was accepted at the prestigious National Academy of Theatre in Oslo, Norway, where he studied acting for three years.