From 1938 Kapp was the organist in Tartu where he ran many famous choirs. After World War II he worked mainly as a composer and taught composition at the State Conservatory of Tallinn from 1944 until his untimely death in 1964. His students included Helmut Rosenvald, Lembit Veevo, Ülo Vinter, Veljo Tormis, Harri Otsa and others.
In 1971 a museum was opened in Suure-Jaani dedicated to the life and work of the Kapp family musicians, including Kapp, his uncle Artur Kapp and his cousin Eugen Kapp.
Works
Incomplete List:
Ööpoeem (for Symphony Orchestra, 1942)
Põhjarannik (Heroic Choral Poem, 1958)
Lembitu (Opera, 1961) - Perhaps Kapp's Magnum Opus; An historical opera based on Estonia's fight for independence in the 13th century, including the Battle of St. Matthew's Day and the eponymous Estonian elder of Sakala County and military leader. The ancient Sakala County included the areas where Kapp grew up, so the themes were particularly close to his heart.[1]
Kevadele (Cantata, 1963)
In addition to these, Kapp also wrote two symphonies (In 1947 and 1955), as well as more than sixty choral and solo songs.
