Kapp's son Eugen (1908–1996) and nephew Villem (1913–1964) became notable composers as well, having studied at the Tallinn Conservatory under direction of the elder Kapp.
Some of Kapp's most enduring works are the 1899 overtureDon Carlos and the 1900 cantataParadiis ja Peri ("Paradise and Peri"), both of which are large scale works that prominently feature the organ. He is possibly best recalled for his oratorioHiiob ("Job") and Metsateel ("On A Road Through The Woods"), a piece for solo voice. Kapp's work is abundant and diverse and covers many classical genres. He wrote five symphonies, five concertos, overtures, four orchestral suites, in addition to the above.
After the Soviet invasion of Estonia during World War II, Kapp was forced to resign his position as a composer and retired to Suure-Jaani. He died there in 1952 at the age of 73. His professional career spanned more than five decades. His last two major works were the overture "To the Party" (1947), the Symphony No. 4 (dedicated to the 30th anniversary of the Soviet Young Communist League, 1948), and the Symphony (Cantata-Symphony) No. 5 (Peace Symphony).
In 1998, the annual Suure-Jaani Music Days festival was founded to celebrate Artur Kapp's musical legacy, as well as that of his sons and fellow composer Mart Saar (1882-1963), who was also from the area. The Festival is organized by the Eesti Kontsert in conjunction with the town of Suure-Jaani and the International Artur Kapp Society. The venues for performances include Lutheran and Orthodox churches, the Kapp Museum, and the song festival stage.