His creative significance is thrown into deep relief by the musical achievements related to the National Theatre: the birth of the Hungarian national opera, the prize-winning arrangements of two of the period?s most influential poems, Kölcsey?s Himnusz [Hymn] and Vörösmarty's Szózat [Appeal] (functioning as a second national anthem), the spectacular blossoming of popular plays and autonomous male choruses, and the first heyday of song composition inspired by folklore. Egressy made an important contribution to each of these developments, which were of collective significance. With his untiring efforts even in the hardest years following the war of independence he was one of the pioneers of Hungarian composition of the 19th century.