Abstract: The historical population register of Norway contains data on the country's population from 1800 to 1964. Information on the country's population from 1964 to the present is collected in the Central Population Register. The historical register consists of these metric books and civil records, filling in the gaps between population censuses conducted every ten years. In 1801 and, beginning in 1865, these censuses were nominative, that is, contained the names of people. This article is devoted to the problems of linking census records and metric books (record linkage) from 1800 to 1920. Special attention is paid to the identification of individuals and the difficulties of linking records. The main problem is to identify a person by the records belonging to different years, in terms of a significant number of namesakes and variations in the fixation of their names, as well as age. The creation of stable identifiers for individuals and the procedure for linking records from various sources required the development of new software combining automatic and manual methods. Analysis of local databases allows us to hope for successful linking from 2/3 to 90% of records for various periods and regions of the country. The historical register of Norway is unique in its coverage of the territory and the variety of historical sources related to it.