sentences:  In Sweden proletarian literature became known in the 1910s.Early pioneers were Dan Andersson and Martin Koch.Proletarian literature became widely known in the 1930s when a group of non-academic, self-taught writers like Ivar Lo-Johansson, Eyvind Johnson, Jan Fridegård and Harry Martinson appeared writing about the working-class, often from the perspective of a young man.