Welschenrohr (French: Rosières) is a former municipality in the district of Thal in the canton of Solothurn in Switzerland.

Welschenrohr had an area, as of 2009[update], of 12.99 square kilometers (5.02 sq mi).

[5] The former municipality is located in the Thal district, along the road between Balsthal and Moutier.

The blazon of the municipal coat of arms is Per bend sinister Gules and Argent a Cramp fesswise counterchanged.

[8] Most of the population (as of 2000[update]) speaks German (1,105 or 94.4%), with Albanian being second most common (18 or 1.5%) and French being third (10 or 0.9%).

[9] As of 2008[update], the gender distribution of the population was 50.4% male and 49.6% female.

[7] The age distribution, as of 2000[update], in Welschenrohr is; 88 children or 7.5% of the population are between 0 and 6 years old and 206 teenagers or 17.6% are between 7 and 19.

The greatest number of single family homes (79) were built between 1946 and 1960.

[8] The historical population is given in the following chart:[4][13] In the 2007 federal election the most popular party was the SVP which received 29.71% of the vote.

In the federal election, a total of 472 votes were cast, and the voter turnout was 54.3%.

[8] There were 566 residents of the municipality who were employed in some capacity, of which females made up 45.6% of the workforce.

In 2008[update] the total number of full-time equivalent jobs was 263.

The number of jobs in the primary sector was 33, of which 32 were in agriculture and 1 was in forestry or lumber production.

In the tertiary sector; 9 or 12.5% were in wholesale or retail sales or the repair of motor vehicles, 6 or 8.3% were in the movement and storage of goods, 9 or 12.5% were in a hotel or restaurant, 10 or 13.9% were the insurance or financial industry, 1 was a technical professional or scientist, 8 or 11.1% were in education and 13 or 18.1% were in health care.

[8] From the 2000 census[update], 720 or 61.5% were Roman Catholic, while 296 or 25.3% belonged to the Swiss Reformed Church.

The education system in the Canton of Solothurn allows young children to attend two years of non-obligatory Kindergarten.

All the lower secondary students from Welschenrohr attend their school in a neighboring municipality.