This thesis has examined unmarried fathers in two parishes of Umeå in northern Sweden during the period 1897-1937. The main focus is on the consequences that ensued the legislation that formalized men’s obligations towards children born out of wedlock, which was passed on June 14th, 1917. The period chosen for this thesis analysis is twenty years before and after 1917. This enables a comparison between the society of the late 19th century and a society smitten by a modernised social reform in the early 20th century. To investigate the subject matter, records of birth and baptismal have been studied with a primary focus on patterns concerning fathers of illegitimate children. Both parishes presented a considerably small number of unmarried fathers compared to married men, throughout the entire period. The town of Umeå had the largest overall share in comparison with the countryside. It was pre-supposed, based on previous research, that the social class to which most unmarried fathers belonged, were in the lower ranks of society. This turned out to be an accurate assumption based on statistics from both parishes presented in this thesis. The statistics did not present any men from the upper class as fathers of children born out of wed-lock. Monetary as well as societal pressure were identified as possible explanations why some men avoided fathering illegitimate children. All in all, the legislation was interpreted as some-what successful in Umeå; achieving an apparent reduction in total shares of unknown fathers, a rising number of pledged paternities and presenting a few examples of men sentenced to fa-therhood in court. The legislation also provided unmarried women with a voice in legal matters concerning their illegitimate children.