[3] After the war the position he had taken against the annexation of Belgium hindered his professional advancement within the university establishment, but he was able to obtain work as a private tutor.
The idea originated at a meeting of the French Institute in Berlin and was seen as a response to the retreat into individual nationally defined intellectual trenches that had only intensified since 1918.
In 1929 the noted Medievalist Robert Holtzmann moved to the Berlin institute, and saw that Sproemberg was ideally placed to support the German end of the operation because of the extensive network of suitable contacts he had built up during more than ten years as a well regarded private tutor.
[1] In January 1933, following months of political deadlock in parliament (the "Reichstag"), the Nazis took power and lost no time in transforming Germany into a one-party dictatorship.
At some stage the authorities determined that on his mother's side Heinrich Sproemberg had Jewish ancestry and during the later 1930s he found himself denounced as a non-Aryan and a "Mixed-blood".
The war's end had seen what remained of Germany divided into four military occupation zones (with separate, more complicated, provision made for the administration of Berlin itself).
It was in this version of Germany that Heinrich Sproemberg lived out the rest of life and built for himself a late flowering career as a university professor.
[3] Sproemberg moved to Rostock in 1946, holding a teaching chair as professor in Medieval and Modern History until 1950, also identified during this period as "seminar director".
[4] Arriving at Rostock at a time of intense reconstruction, he engaged in a root and branch renewal in terms of personnel and teaching methods.
After the individual states ("Lander") were dissolved as separate administrative units in 1952, this became the only surviving regional historical institute of its kinds in the German Democratic Republic.
[3] Nevertheless, as one of those academics, who also included Ernst Bloch, who resolutely refused to involve themselves in politics or become members of government sponsored quasi-political organisations, he became increasingly vulnerable to attacks.
His "Contributions to Belgian-Dutch history" ("Beiträge zur belgisch-niederländischen Geschichte") was rejected for publication as "not Marxist" in 1957 (though it was eventually published two years later).