This dissertation examines the development of the surname system in the province of Uppland, Sweden, with special reference to Uppsala, as well as providing a description of the origins of the surname system in Sweden as a whole. The period in question is 1630–1730, in certain cases extending to 1760. The localities studied are the city of Uppsala, several northern Uppland brukssamhällen (small countryside communities centered around foundries) and two parishes in the countryside.

In the mid-17th century, bynames are as yet rare in Uppsala, the main exceptions being university teachers and students. From this time, the share of men bearing bynames, as seen in the tax rolls of the city outside the jurisdiction of the university, increases rather quickly, reaching about 70 % in 1720. Among workers and craftsmen at the foundries this development occurs considerably later. In the countryside proper, only a small fraction of the population has been affected by this development even as late as 1760.

Women are relatively scarce in the sources and, when recorded, are often listed indirectly (e g Rolof’s widow), or only by their first name. To a certain degree women become more frequently noted with bynames after 1700.

The bynames in Uppsala follow a pattern determined by social class. Thus, bynames spread first in higher social strata. As regards the social distribution of formation types in the city, humanist names (e g Stenius) are to begin with borne excusively by people with academic background, and dithematic names (e g Uppman) are up until about 1670 in principal found in higher social strata. At the end of the 17th century the pattern becomes less clear. Among workers and servants, however, byname bearers remain in the minority as late as 1730.

Surnames gradually become more common. They are easiest to find in higher social strata. This can partially be explained by the nature of the sources, but it remains likely that they nevertheless give a rather accurate picture of reality.