This is a readme file for the data set published in conjunction with the article: Seppo Eskola, Jaakko Tahkokallio: "How many fragments? The original extent, the nineteenth-century losses, and the present size of the Swedish-Finnish medieval book fragment collections" The data has been produced as part of the ERC-funded project BOMPAC (Books of the Medieval Parish Church, Grant number: 948497) in 2021–2024. The data was compiled to its final form in September 2024. Contributors: Jaakko Tahkokallio (PI, supervision of data creation, processing FM and MPO data) Seppo Eskola (processing FM data, MPO data, and data for incunabula and early printed works; supervision of data creation) Holger Kaasik (parsing and enriching MPO data) Susanna Rämö (FM and MPO data collection and processing; data collection for Finnish fragments of prints) Maria von Hertzen (FM and MPO data collection and processing) Robert Stjernberg (FM data collection) Daniela Fougstedt (FM data collection) General information: This readme file contains information on the dataset published in conjunction with the above-mentioned article. There are three data files (csv format) and an appendix (pdf format) with tables summarising the data. The scope of the first two data files is defined by two seventeenth century catalogues, composed in 1628 and 1637, respectively, and introduced in the article. The 1628 catalogue lists the Vasa-era regional accounts of the Swedish realm. The 1637 catalogue lists the accounts produced by the central administration. Both files contain data gathered from i.) the aforementioned catalogues (indicated 1628/1637); ii) related data gathered from modern archival systems and iii) related data on the medieval fragment covers of the accounts. The third file contains a list itemising each fragment in either the Swedish or Finnish collections (that we have been able to identify). For additional contextualising information, please see below and consult the article. File 1: Data with the 1628 catalogue (Swedish National Archives, Kammarens ämbetsarkiv, D II Ser I:2; see article) as a starting point. The catalogue covers nine regions of the Swedish realm and, additionally, a limited number of accounts of the 1613 "Älvsborg lösen"". For each region data are given for account units, registers (=account booklets), and fragments (as determined by available metadata). Mostly the columns are self-explanatory, but a few require clarification. For Finland, three extra categories of "Åland", "Österbotten", and "Kemi Lappmark" are included, as these enable adjusting the data between Finland and Norrland for more accurate comparisons between historical and modern data series (historically, the aforementioned areas were administratively handled under Norrland, whereas today, the sources related to these areas are a part of the Finnish archives). Additionally, a series labelled "Finland, Fogderäkenskaper, allmänna räkenskaper 2024" is given for separating the regional and central account booklets in the Finnish modern account series. Finally, a series labelled "Registers 1999" (Brunius 2000) is provided. This is based on interpolating data from the article Jan Brunius, “Landskapshandlingarna i Kammararkivet : Från Kammarens Register till Databas,” in Arkiv, Samhälle och Forskning, vol. 2000:1 (Stockholm: Svenska arkivsamfundet, 2000), 7–27. See diagram on page 23. Column headers: Year Uppland, Units 1628 Norrland, Units 1628 Södermanland och Närke, Units 1628 Västmanland och Dalarna, Units 1628 Småland, Units 1628 Västergötland, Värmland och Dalsland, Units 1628 Östergötland, Units 1628 Finland, Units 1628 Livland, Units 1628 Älvsborg lösen 1613, Units 1628 Uppland, Registers 1628 Norrland, Registers 1628 Södermanland och Närke, Registers 1628 Västmanland och Dalarna, Registers 1628 Småland, Registers 1628 Västergötland, Värmland och Dalsland, Registers 1628 Östergötland, Registers 1628 Finland, Registers 1628 Livland, Registers 1628 Älvsborglösen 1613, Registers 1628 Uppland, MPO signa Norrland, MPO signa Södermanland och Närke, MPO signa Västmanland och Dalarna, MPO signa Småland, MPO signa Västergötland, Värmland och Dalsland, MPO signa Östergötland, MPO signa Livland, MPO signa Uppland, Units 2024 Norrland, Units 2024 Södermanland och Närke, Units 2024 Västmanland och Dalarna, Units 2024 Småland, Units 2024 Västergötland, Värmland och Dalsland, Units 2024 Östergötland, Units 2024 Livland, Registers 2024 Åland, Units 2024 Österbotten, Units 2024 Kemi lappmark, Units 2024 Åland, Registers 1628 Österbotten, Registers 1628 Kemi lappmark, Registers 1628 Registers 1999 (Brunius 2000) Bailiffs' records signa, Hki, all Bailiffs' records signa, Hki, General section Bailiffs' records signa, Hki, Åland series Bailiffs' records signa, Hki, Österbotten series Finland, fragment covers currently File 2: Scope of the data defined by the 1637 catalogue (Swedish National Archives, Kammarens ämbetsarkiv, D II Ser I:4; see article). The catalogue lists accounts of various series produced by the central administration. The term “register” is used to indicate an account booklet. Numbers of registers are enumerated for the series in the 1637 catalogue and equivalent modern archival series. In addition, fragments listed in the MPO with links to these series (as far as can be determined) are enumerated. There are three columns that contain no data: "Registers 2024, Salpeterbruk", "Registers 2024, Ransakninger", "MPO signa, Ransakningar". This is due to the fact that no modern data that would correspond to these 1637 catalogue series was found. The series are small and have little effect on the data as a whole but, instead of removing them, they have been left in the file to highlight places where no comparison data has been found. Column headers: Year Registers 1637, Räntekammarböckerna Registers 1637, Varuhus och handling och Provianträkenskaper Registers 1637, Lokala tullräkenskaper Registers 1637, Skeppgårdshandlingar Registers 1637, Klädkammarräkenskaper och Skinkammaren Registers 1637, Arkliräkningar Registers 1637, Militieräkningar Registers 1637, Löningsregister Registers 1637, Salpeterbruk Registers 1637, Ransakninger Registers 1637, Förläninger Registers 2024, Räntekammarböckerna 1526-1630 Registers 2024, Varuhus och handling 1538-1620 Registers 2024, Provianträkenskaper Registers 2024, Lokala tullräkenskaper Registers 2024, Skeppgårdshandlingar 1540-1640 Registers 2024, Klädkammarräkenskaper 1531-1623 Registers 2024, Skinnkammaren 1540-1619 Registers 2024, Arkliräkninger Registers 2024, Militieräkninger Registers 2024, Löningsregister Registers 2024, Salpeterbruk Registers 2024, Ransakninger Registers 2024, Förläningsregister MPO signa, Räntekammarböckerna 1526-1630 MPO signa, Varuhus och handling 1538-1620 MPO signa, Provianträkenskaper MPO signa, Lokala tullräkenskaper MPO signa, Skeppgårdshandlingar 1540-1640 MPO signa, Klädkammarräkenskaper 1531-1623 MPO signa, Skinnkammaren 1540-1619 MPO signa, Arkliräkenskaper MPO signa, Militieräkenskaper MPO signa, Löningsregister MPO signa, Strödda militiehandlingar före 1631 MPO signa, Ranskakningar MPO signa, Förläningsregister File 3: This file lists each fragment in the Swedish and Finnish collections that has been identified, with one row representing a fragment. First, the “Swedish” fragments are listed (i.e., the MPO), then the “Finnish ones” (The FM, two fragments at the Finnish National Archives, and any fragments of early printed works that we have determined are likely to have been used as covers for Finnish account booklets. The columns, with brief explanations when needed, are listed below. File_index: self-explanatory "Collection"_tag: labels every fragment as either Swedish or Finnish Database_or_holding_institution: self-explanatory Material: Parchment or paper MS_or_print: labels each fragment as originating from either a manuscript or a printed work Fragment_number_or_shelf_mark_or_id: an identifier for each fragment Cover_status: data on whether a fragment forms the main part of a cover or a smaller section Row_exclusion: rows that we suggest should be excluded from consideration Exclusion_criteria: criteria for the previous column Archival_group: labels fragments according to the archival group they belong to (when known) Archival_series: a more exact label than previous Account_year_tag: whether fragment has an account year in the metadata Account_year: year of the account the fragment was used to cover Additional_information: any possible additional information Leaves: number of leaves for each fragment. Leaves_uncertainty: When there is uncertainty over the number of leaves, this column contains either the value "?" or "At least 1".