[1][2] Both her parents were assimilated, non-observant Jews; her father had Hedi baptised to make sure that she would have protection from antisemitic shopkeepers during the starvation caused by the First World War.
She was sent to a progressive school in Vienna founded by the Polish-Jewish feminist Eugenia Schwarzwald, at whose home Hedi met such figures as the painter Oskar Kokoschka and the architect Adolph Loos.
Through contacts in Whitehall, Dr Simon sent his daughter to Newnham College, Cambridge, where she continued her studies, but switched to Moral Sciences (philosophy) under Ludwig Wittgenstein.
The Keunemans joined the USP, which was fiercely anti-colonial until the invasion by Hitler of the Soviet Union, thereafter advocating co-operation with the colonial regime against the common enemy, fascism.
Between 1940 and 1942, Hedi Keuneman taught at University College, Colombo and at the Modern School initiated by another communist emigrant and India League veteran, Doreen Young Wickremasinghe.
She was active in the Friends of the Soviet Union and, with shoulder-length black hair and sometimes barefoot in a red sari, distributed pro-communist literature and addressed meetings among English-speaking supporters.
Following end of the war in 1945, Hedi Keuneman returned to Europe to meet her mother—as a communist, she was barred from entering the United States (where her father had died in 1942).
Hedi Stadlen was survived by her sons Nicholas, a High Court judge (who holds the record for the longest speech in British legal history—119 days), and Godfrey, a senior civil servant in the Home Office.