Carl Natanael Rexroth-Berg (9 February 1879, Stockholm – 14 October 1957, Stockholm) was a Swedish composer.
Berg trained in veterinary medicine and began learning music by teaching himself. He later studied at the Stockholm Conservatory as the pupil of Johan Lindegren. Until 1939, he served as a veterinarian in the Swedish Army and afterwards he became a freelance composer.
His output included five operas, three ballets, five symphonies as well as several symphonic poems, a piano concerto, a violin concerto, a serenade for violin and orchestra, a piano quintet, ballades, lieder, and pieces for piano.
Saul och David, 1907
Eros vrede, 1907
Traumgewalten, symphonic poem, 1910
Leila, opera, 1910
Mannen och kvinnan, 1911
Predikaren, 1911
Symphony No. 1 Alles endet was entstehet, 1913
Varde Ljus, symphonic poem, 1914
Älvorna, ballet, 1914
Israels lovsång, 1915
Symphony No. 2 Årstiderna, 1916
Symphony No. 3 Makter, 1917
Piano Quintet, 1917
Die badenden Kinder, 1918
Violin Concerto, 1918
Symphony No. 4 Pezzo Sinfonico, 1918
Sensitiva, ballet, 1919
String Quartet, 1919
Hertiginnans friare, ballet, 1920
Serenade for Violin and Orchester, 1923
Symphony No.