Jurisdictions in Finland 1800-1900
General
In the maps, the jurisdiction borders in Finland are shown in years 1800, 1820, 1840, 1860, 1880 and 1900. The area of the district court (käräjäkunta / tingslag) is here called district. The tuomiokunta / domsaga, or the area that was given to one judge to rule consisted of one or several districts. Here, it will be called jurisdiction. Until 1868, there was also a larger area laamannikunta / lagsaga, that consisted of several jurisdictions. It is used here to illustrational purposes only: after 1868 the county level (lääni, Sv. län) is used instead.
Why the borders are shown in a map instead of a list or a table? Traditionally, the country consisted of parishes with some underlying areas called chapels, as we talk about congregational entities. In time, some of the chapels became parishes and inside them new chapels were established. Sometimes land was transferred between units, and the borders are on the move in history.
On the other hand, the districts consisted of one ore several "administrational parishes" or even of parts of them. Administrational parishes did not coincide with the congregational ones. When a border change happened between parishes and chapels, there was not necessarily any change in judiciary borders. So the list would be a collections of exceptions and their exceptions, and it would be very long. And what's more, we have no systematic data for border changes for the whole realm.
In map view, the anomalies we know are taken into account, and the area inside one jurisdiction would be part of it no matter the congregational changes inside it. Mind though, that we don't know all anomalies and when they were changed. So if the place of your interests is near the domsaga border, you might want to check the neighbour, too.
Using the maps service
The little map gives an overview of the situation. Clicking the map opens the larger map. You can zoom it by the mouse scroll. Drag the picture and to find your place of interest. The jurisdictions have an abbreviation, which is explained in the right side of the picture. If there are changes between two years, below the map is the explanation of the jurisdictions, districts and the changes in them between those years.
When you find the right jurisdiction, use it as a filter in your search. The name in the abbreviations list is the same as in the filter (in the brackets is respective name in Swedish, which is the form you will find in the documents). The name in the explanation text may vary somewhat. There, the Swedish name is used if it is considerably different than the Finnish one; plain genetives are shown only once (i.e. "Rantasalmen" [tuomiokunta] should be "Rantasalmi" [domsaga] but only the former is used here.
Not all court books are included in the search. The ones from Åland / Ahvenanmaa, Suur-Savo, Sääksmäen ylinen and Sääksmäen alinen jurisdictions were destroyed in the fire of Turku 1827. There could be other minor gaps in the series. The books of the jurisdictions that were ceded to Soviet Union (Jääski, Kurkijoki, Käkisalmi, Ranta, Salmi, Sortavala, Äyräpää and their predecessors) are held in another context and not digitized. The so called "old towns" had the city court (raastuvanoikeus, sv. rådstuvurätten) and their court records are not yet searchable.
The base map is the municipalities border map of 1937. So it will show the municipality (parishes and chapels alike became municipalities after 1868) borders of that year. There will be many names that didn't exist in the year the border map is for. Mind that even if a spatial change is marked in the map, it is not explained in the text. Hopefully we can offer that sometimes in the future, but this kind of research was not in the scope of this project.