Background
Castonier was the daughter of the painter Felix Borchardt and spent her early childhood in Dresden until her family moved to Paris.
Castonier was the daughter of the painter Felix Borchardt and spent her early childhood in Dresden until her family moved to Paris.
Her grandfather was Jewish. She wrote satires in the weekly paper Die Ente, but during the Nazi period she went in exile to Vienna and after the Anschluss in 1938 through Italy and Denmark to London. Here she wrote children"s books and also a book about Christian opposition to the Nazis.
In London she was also a correspondent for the News Chronicle and the New Statesman and also for emigrant newspapers like the Pariser Tageszeitung and the Wiener Tageblatt.
In 1944 she worked as a farmhand in Hampshire. From 1950, she also corresponded regularly with Mary Tucholsky, the widow of writer Kurt Tucholsky.