With her husband, she would author two popularizing books on Dutch history that established their national fame: De lage landen bij de zee ("The Low Countries by the sea", 1934), a Marxist national history that reached a wide audience, and Erflaters van onze beschaving ("Testators of our civilization, four volumes, 1938–1940), a collection of 36 biographies of famous Dutchmen (and one woman, Betje Wolff) of bygone centuries, seventeen of them written by Romein-Verschoor.

A study of female authorship in the Dutch language since 1880, the work was reprinted in 1977 and well received by the resurgent feminist movement of the 1970s.

In the following Cold War era, they were politically isolated as non-affiliated communists.

Romein-Verschoor always remained true to the communist ideal, but publicly defended Boris Pasternak and denounced socialist realism as a "constant distorting of reality to match theory".

[1] Romein-Verschoor wrote an introduction in the First Edition of "Het Achterhuis," Anne Frank's original 1947 printed book about her diary, later reprinted as The Diary of a Young Girl.