Krása, whose primary influences were Mahler, Schoenberg and Zemlinsky, also felt an affinity with French music, especially the group of composers known as Les Six and made a number of trips to France to study under Roussel while he lived in Berlin.

Krása was sent to the Theresienstadt ghetto where he reworked Brundibár with the available cast “and scattered salt of staging”, who then performed it 55 times in the camp, with excerpts featured in the infamous propaganda film made for the Red Cross in 1944.

While he was interned in the ghetto, Krása was at his most productive, producing a number of chamber works including Tans, Theme with Variations, and Pascaglia and Fugue, [2] although, due to the circumstances, some of these have not survived.

His Three Songs after poems by Arthur Rimbaud, Čtyřverší, Vzrušení and Přátelé, sung by Christian Gerhaher, appear on the CD Terezín - Theresienstadt initiated by Anne Sofie von Otter, Deutsche Grammophon, 2007.

[5] As part of the same series his opera Verlobung im Traum (Betrothal in a Dream) and Symphonie appeared in recordings by the Deutsches Symphonie-Orchester Berlin conducted by Lothar Zagrosek and Vladimir Ashkenazy respectively, label: Decca 455 587–2.