Karel Weis (sometimes spelled Weiss) (13 February 1862 – 4 April 1944) was a Czech composer and folksong collector. He was born in Prague.
Weis studied at the Prague Conservatory from 1873–1878, the Prague Organ School from 1878–1881, and privately with Zdeněk Fibich. He was organist of St Štěpán and choirmaster at the main synagogue of Prague (1881–1882), a teacher at the music school of the Moravan choral society in Kroměříž (1882–1883), a violinist in the National Theatre orchestra, Prague (1883–1886) and conductor of the Švanda Theatre Company in Prague and Brno (1886–1887). Subsequently he edited the monthly Hudební květy (1895–1899), conducted the Academic Orchestra (1898) and worked as an accompanist (1896–1904), mainly for the violinist František Ondříček.
From 1896 to the end of his life in Prague in 1944, Weis gave most of his attention to collecting and arranging folksongs, particularly those of the Chodsko region, south Bohemia. Between 1928 and 1941, he published a fifteen volume collection of folk songs, Český jih a Šumava v písni. The collection is his only work to have stood the test of time.
Weis’s large and varied output was influenced mostly by Smetana and Dvořák. Among his many compositions are eleven operas, (three in Czech, and eight, of which six are operettas, in German), five of which premiered at the Prague State Opera. Czech nationalists however criticised him for setting German texts.[1]