Moster is a former municipality in the old Hordaland county, Norway. The municipality existed from 1916 until its dissolution in 1963. The area is now part of Bømlo Municipality in the traditional district of Sunnhordland in Vestland county. The administrative centre was the village of Mosterhamn, where the Old Moster Church is located (the oldest surviving stone church in Norway).
Prior to its dissolution in 1963, the municipality was the 577th largest by area out of the 705 municipalities in Norway. Moster Municipality was the 471st most populous municipality in Norway with a population of about . The municipality's population density was and its population had increased by 5.3% over the previous 10-year period.
The municipality of Moster was established on 1 July 1916 when the old Finnaas Municipality was divided into the three new municipalities as follows:
During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee. On 1 January 1963, a large municipal merger took place and the following areas were merged to form a new, larger Bømlo Municipality:
The municipality (originally the parish) is named after the island of Moster () since the first Moster Church was built there. The meaning of the first element is uncertain. It may come from the word which means "mossy swamp", likely because the island is marshy. It could also come from the word which means "pleased" or "large amount", possibly referring to the fact that the island is very hilly. Another possibility is that it comes from the word which means "mane".
The Church of Norway had one parish () within Moster Municipality. At the time of the municipal dissolution, it was part of the FinnÃÂ¥s prestegjeld and the Søndre Sunnhordland prosti (deanery) in the Diocese of Bjørgvin.
The municipality encompassed the southeastern part of the island of Bømlo and the island of Moster as well as many surrounding islets. The highest point in the municipality was the tall mountain Siggjo. Fitjar Municipality is located to the north, Stord Municipality is located to the northeast, Valestrand Municipality is located to the southeast, Sveio Municipality is located to the south, Bømlo Municipality is located to the southwest, and Bremnes Municipality is located to the northwest.
While it existed, Moster Municipality was responsible for primary education (through 10th grade), outpatient health services, senior citizen services, welfare and other social services, zoning, economic development, and municipal roads and utilities. The municipality was governed by a municipal council of directly elected representatives. The mayor was indirectly elected by a vote of the municipal council. The municipality was under the jurisdiction of the Sunnhordland District Court and Gulating Court of Appeal.
The municipal council of Moster Municipality was made up of 17 representatives that were elected to four year terms. The tables below show the historical composition of the council by political party.
The mayor () of Moster Municipality was the political leader of the municipality and the chairperson of the municipal council. The following people have held this position: