|Incorporated into||Notodden in 1964|
The parish of Hitterdal was established as a municipality January 1, 1838 (see formannskapsdistrikt). Notodden was separated from Heddal both as a city and a municipality of its own, in 1913. Heddal was subsequently merged with Notodden January 1, 1964. The Heddal clerical district consists of two parishes: Hitterdal and Lisleherad.
The Old Norse form of the name was Heitrardalr. The first element is the genitive case of a former name of the River Heitr, now known as Heddøla, a tributary of the Skien River. The last element is dalr meaning dale or valley. The original meaning of the river name is unknown. Until 1918 the name was written Hitterdal or Hiterdal. From 1918 on, the name has been Heddal.
Nearby rivers include the River Hjartdøla.
Notable people from Heddal
- Egil Bergsland (1924–2007), Norwegian politician for the Labour Party
- Thorolf Bugge (1879–1935), Norwegian trade unionist and politician
- Olea Crøger (1801–1855), Folklore collector, who published old folk tunes
- Sigmund Groven (born 1946), Norwegian classical harmonica player
- Hans Herbjørnsrud (1938-), Author of short stories.