Hermann Robert Richard Eugen Kasack (24 July 1896 – 10 January 1966) was a German writer.

Kasack was born in Potsdam as the only child of a doctor, he studied from 1914 to 1920 national economics and history of literature at the Humboldt-Universität zu Berlin.

In 1941, he succeeded Oskar Loerke as literary editor in the S. Fischer Verlag, and took consequently over the direction of the publishing house when Peter Suhrkamp was arrested from 1944.

[2] A 1957 review stated:But it took the extraordinary event of 1947, the publication of his first novel, Die Stadt hinter dem Strom, to catapult his name into the literary limelight and lift it to true prominence.

He wrote a libretto for an opera Die Stadt hinter dem Strom, which was composed by Hans Vogt and premiered at the Hessisches Staatstheater Wiesbaden in 1955 as part of the Internationale Maifestspiele Wiesbaden.