Ruschein, a municipality in Surselva, Switzerland with Sursilvan dialect of Romansha Romance language recognized as the national language of Switzerlandas its official language, has the lowest population in 1850 while its highest number of population is 356 in the year 2000.
Romansh has been recognized as a national language of Switzerland since 1938, and as an official language in correspondence with Romansh-speaking citizens since 1996, along with German, French and Italian. 
