The letters written by king Gustav Vasa in the Swedish Diachronic Corpus are retrieved from Språkbanken's collection 'Gustav Vasas brevproduktion', containing letters written by king Gustav Vasa in the time period 1521--1525. If you want to know more about the Swedish Diachronic Corpus, the following SweClarin reports may be of interest: SCR-03-2019 Towards a Swedish diachronic corpus: Intended content, structure and format of version 1.0 Eva Pettersson & Lars Borin url: https://sweclarin.se/sites/sweclarin.se/files/outline-swedish-corpus.pdf SCR-02-2019 Swedish diachronic texts: Resources and user needs to consider in a Swedish diachronic corpus Eva Pettersson & Lars Borin url: https://sweclarin.se/sites/sweclarin.se/files/swedish-historical-texts_3.pdf SCR-01-2019 Characteristics of diachronic and historical corpora: Features to consider in a Swedish diachronic corpus Eva Pettersson & Lars Borin url: https://sweclarin.se/sites/sweclarin.se/files/diachronic-corpora-sweclarin-v3.pdf