The dissertation was subsequently lost and Torhorst's contribution was for many decades overlooked; but in the twenty-first century mathematics scholars are happy to acknowledge and celebrate her work.

[3][5] Marie Torhorst was born at the end of the so-called "Year of the Three Emperors" in Ledde, then as now a sleepy village in the flat countryside west of Osnabrück.

There were still vanishingly few women working in high-level academic research at this time, however, and at least one commentator has identified "a lack of confidence in her own mathematical ability" in her autobiography.

[1][4] In 1923 Torhorst took on the headship of a private business school for the "Frauenerwerbs- und Ausbildungsverein" (loosely, "Women's employment and training association") in Bremen.

[1] She also teamed up with politically like-minded teacher colleagues, during this period, to organise evening courses for young people who had been excluded from state schools in the area.

[14] Her political and feminist beliefs had been deeply rooted in Torhorst's personal values and life choices since at least as far back as the First World War, but it was only in 1928 that she became a member of the Social Democratic Party (SPD).

[1] It was in the same year that she joined the "Freie Lehrergewerkschaft Deutschlands" / FLGD, a teachers' trades union committed to socialist principals.

In 1929 Karsen took the bold step of turning it into a "Gesamtschule" (loosely, "comprehensive school"), intended to educate children displaying the widest possible range of abilities.

A progressive school in a traditionally left-wing district of Berlin named in honour of Karl Marx was, unsurprisingly, high on the National Socialist hate list.

The teaching staff were dismissed, and when the school reopened later that year it was with a new name, a new set of teachers, and a large swastika flag hanging in the main hall.

She later found a job as an appointments administrator at the Berlin University Hygiene Institute, and another as a typist in the travel office correspondence section of an American Express (AMEXCO) branch.

According to her own understanding set out in a letter to a friend at the time, changes to the law implemented in 1934/35 meant that she was unable to litigate the matter.

As soon as she lost her teaching job at beginning of 1933 she became an activist member of "Parole", a locally based resistance group in Berlin-Neukölln.

[16] The authorities seem to have known (or suspected) that the teachers who had lost their jobs when the Karl Marx School in Neukölln had been taken over would (or might) have kept in touch and formed some sort of a resistance organisation.

Within Germany, government persecution of political opponents and of Jews intensified progressively till the Shoah reached its brutish nadir in 1942.

Sources are silent over what happened to the people she had been hiding, but Marie Torhorst herself was detained and taken to the "Hallendorf labour camp" by Watenstedt, near Braunschweig.

The western two thirds of Germany had ended up divided into four military occupation zones, administered respectively by the British, the Americans, the French and the Soviets.

The region surrounding Berlin, along with the ruins and rubble comprising eastern part of the city itself, were administered as the Soviet occupation zone.

Torhorst had spent the Hitler years based in Berlin and she now made her choice: she joined the (no longer outlawed) Communist Party in or before January 1946.

[19] The recently launched women's weekly magazine "Die Frau von heute" carried her portrait on its front page, accompanied by the headline "Frauen als Minister ..... [habe] Deutschland noch nicht gesehen" (loosely, "Women as ministers .... a new experience for Germany" There was a brief article spelling out that her appointment was justified by "long years of specialist knowledge", but also acknowledging that "as a woman she ... [would be] exposed to exceptional levels of criticism".

Even though it had in the past been the case that "a few thousand of her gender-comrades, who came from the more favourably positioned classes, found their way into some of the higher professions, such as medicine, academic life or equivalent levels in public service", Torhorst's appointment as a minister showed that "the whole situation for the female gender has changed fundamentally, since their equality of value and equality of entitlement with men" was officially recognised, and thereby their "gender-subservience" had been done away with.

[20] An interesting insight into her education philosophy as minister comes from a surviving record of a "conversation" that Torhorst held with an American delegation on 27 June 1947, shortly after her appointment to ministerial office: "The most important work ... would be implementation of the law to democratise German schools".

The two sisters, still unmarried, childless, and still – in their different ways – deeply engaged in the politics of education, made their home together in Weimar, which till 1952 was the seat of the state government for Thuringia.

Isolde Oschmann was a former Kindergarten teacher who turned out to be very much less of a hands-on education minister that Torhorst had been: her footprint on East German history remained slight despite her having held ministerial office for more than a year.

[16][19] Torhorst then served, briefly during 1951/52, as political secretary with the East Berlin office of the "Internationale Demokratische Frauenföderation" (IDFF / "Women's International Democratic Federation").

In 1952 she joined the East German Education Ministry as head of the department for cultural relations with foreign countries, a position she retained till 1957.

Beyond the world of education, she also served between 1957 and 1960 as an honorary deputy president of the "Demokratischer Frauenbund Deutschlands" (DFD / "(East) German Democratic Women's League".

Those on whom she submitted reports included her cousin, the respected professor of church law Rudolf Smend, the popular historian Wolfgang Leonhardt and the journalist Stephan Grzeskowiak.

She was indeed unusual among Stasi informants in her willingness to submit unsolicited advice, for instance concerning books from the west which should probably not be permitted to circulate in East Germany, or ways in which East German radio programmes might more effectively counter the "western propaganda" broadcast by the U.S. backed RIAS (radio station) from West Berlin.