Holtålen is a municipality in Sør-Trøndelag county, Norway. It is part of the Gauldalen region. The administrative centre of the municipality is the village of Ålen. Other villages include Hessdalen, Aunegrenda, Haltdalen, and Renbygda.

The municipality of Holtaalen was established on 1 January 1838 (see formannskapsdistrikt). In 1841, the western part of the municipality was separated to become the municipality of Singsås. This left Holtaalen with 1,885 residents. Then in 1855, the southeastern part of Holtaalen was separated to become the municipality of Ålen, leaving Holtaalen with 809 residents. The spelling of the name was changed to Holtålen in 1921. In 1937, the name was changed from Holtålen to Haltdalen. On 1 January 1972, the municipality of Haltdalen was merged with Ålen to form the new municipality of Holtålen. Prior to the merger, Haltdalen had 778 residents. On 21 April 1989, a small unpopulated part of Røros was transferred to Holtålen.

The Old Norse forms of the name was Holtdalr and (later) Holtáll. The first element is the old name of the Holda river. The last element was (first) dalr which means "valley" or "dale", but this was later (around 1400 AD) replaced by the word áll which means "ditch" or "gully". The form -ålen is the modern finite form of this word. The name of the municipality was spelled Holtaalen before 1938, Haltdalen from 1938 until 1972, and then Holtålen since 1972.

...
Wikipedia