Äänekoski is an industrial city in the province of Central Finland at the southern end of Lake Keitele. The neighboring municipalities of Äänekoski are Kannonkoski, Konnevesi, Laukaa, Saarijärvi, Uurainen, Vesanto and Viitasaari. In the alphabet, Äänekoski ranks last among Finnish municipalities in terms of Finnish names. Östermark (Teuva) and Övertorneå (Ylitornio) are still in Swedish names after Äänekoski.
The independent municipality of Äänekoski was preceded by the secession of the parish from the Laukaa parish: the Äänekoski prayer room was established in 1902. By decision of the Imperial Finnish Senate on March 23, 1906, the Äänekoski parish was established from the beginning of 1907. A new wooden long church was completed in Äänekoski Kirkonmäki in 1906. It was destroyed beyond repair in 1968.
The municipality of Äänekoski was founded in 1911 by separating the northern part of Laukaa municipality and the eastern parts from Saarijärvi municipality into its own municipality. In 1932, the towns of Äänekoski and Suolahti were separated from the municipality, and the name of the then Äänekoski municipality was extended to Äänekoski rural municipality. The township had a population of 3,697 in 1937 and doubled by 1964 (7,619 inhabitants). City rights to Äänekoski were granted in 1973.
Mergers of municipalities
The rural municipality of Äänekoski, whose old town hall is still located at the junction of highways 4 (E75) and 13 in Äänekoski Honkola, was annexed to the Äänekoski township in 1969.
On January 1, 1993, the municipality of Konginkangas, located to its north, was annexed to the city of Äänekoski.
In September 2005, the Äänekoski and Suolahti City Councils and the Sumiainen Municipal Council approved an inter-municipal merger agreement and a proposal to the Government to change the division of municipalities. In May 2006, the Government decided that the municipality of Sumiainen, the city of Suolahti and the city of Äänekoski would be abolished and replaced by a new municipality covering their territories, which would adopt the Äänekoski name and city designation. The new division of municipalities came into force on 1 January 2007. Hannu Javanainen, the mayor of the old Äänekoski city, was elected to lead the new city of Äänekoski. Heli Möller, former mayor of Suolahti, served as Deputy Mayor of Äänekoski. Matti Tuononen has been the Mayor of Äänekoski since 2015.
The former coat of arms of the city of Suolahti was chosen as the coat of arms of the new city of Äänekoski. The coat of arms of Äänekoski's old three post horns fell out of use.