Lars Tiren was one of the leading forest researchers working in northern Sweden during the first half of the twentieth century. He studied forest regeneration and forest production but he was also interested in past land use and how it had affected the forests in northern Sweden. This paper is a review of Tiren's study, “Forestry historical studies in the Degerfors district of the province of Vasterbotten”, published in 1937. The specific aims of this review are to evaluate the main findings, the scientific quality and the possible bias of this study, as well as its value today. Tiren's study included an analysis of forest fire history, and studies of structural changes of old-growth and high-graded forests and of preindustrial forest utilization, and it is based on different methods and sources, including dendrochronology and historical records analyses. Many of Tiren's analyses on intensive uses of the boreal forest prior to commercial forestry are still valid today and his work has influenced research in many fields, for example in forest fire ecology. Tiren's conclusion is, however, somewhat biased since he had a strong objective to demonstrate the poor care of the forest before the twentieth century, and the need for a more production-oriented forest management. Nevertheless, an important value of his work lies in the thorough descriptions of a forest landscape that no longer exists but that he could observe at the beginning of the twentieth century.