Name

The municipality (originally the parish) was originally named Slemdal, after the local valley (Old Norse: Sleimdalr). The first element is likely the old name of a river, the meaning of which is uncertain. The last element is dalr which means "valley" or "dale".^[7]

On 3 November 1917, a royal resolution changed the name of the municipality to Siljan.^[8] This name comes from the old Siljan farm (Old Norse: Seljur) since the first Siljan Church was built there. The name's meaning is uncertain, but it is likely that it comes from the plura form of selja which means "sallow tree" or "willow".^[3]

Coat of arms

The coat of arms was granted on 16 June 1989. The official blazon is "Vert, three saw blades argent palewise in fess" (Norwegian: I grønt tre opprette sølv sagblad). This means the arms have a green field (background) and the charge is a set of three saw blades standing vertically in a horizontal row. The charge has a tincture of argent which means it is commonly colored white, but if it is made out of metal, then silver is used. The green color in the field and the saw blade design symbolize the importance of the timber industry in Siljan. This type of saw blade was used locally throughout history. There were many saw mills located in Siljan along its waterways. The arms were designed by Halvor Holtskog, Jr. The municipal flag has the same design as the coat of arms.^{[9][10][11][12]}

Churches

The Church of Norway has one parish (sokn) within the municipality of Siljan. It is part of the Skien prosti (deanery) in the Diocese of Agder og Telemark.

Mayors

This list is incomplete; you can help by adding missing items. (September 2023)

The mayors (Norwegian: ordfører) of Siljan (incomplete list):

Municipal council

The municipal council (Kommunestyre) of Siljan is made up of 17 representatives that are elected to four year terms. The tables below show the current and historical composition of the council by political party.