It was the final act of a carefully prepared plan. On March 21st 1933, two days before the Reichstag was due to vote on giving Hitler absolute power, the Nazis organized the Day of Potsdam.

Still missing the two thirds majority he needed in parliament, Hitler’s strategy was to woo conservatives into voting with him, while unleashing his stormtroopers on the left-wing opposition.

The fire in the Reichstag a month earlier had given him the excuse he needed to round up and imprison MPs from the communist KPD party. Centrists were intimidated with death threats against them and their families.

Conservatives though, were won over with the promise that Hitler would unite his fascist forces with the traditions of the Prussian monarchy.

The Day of Potsdam was central to this theatre. It marked the opening of a new Reichstag in Potsdam, the seat of the Hohenzollern royal family. In Goebbels’ finely orchestrated ceremony, the streets were decked with the black, red and white flags of the Kaiserreich, not swastikas.

Another key element of the show was the Hohenzollern family itself. At the main ceremony in the Garrison Church, Crown Prince Wilhelm sat with his four brothers behind an empty seat symbolising the throne of his exiled father. Kaiser Wilhelm II, who had been forced to abdicate at the end of the First Word War, was living out his final days in the Netherlands.

Goebbels had staged the show so that the packed audience could see Hitler saluting the former royal family upon his entrance.

The message to national conservatives was clear: you have nothing to fear from us, we are working to restore the old German order of things. The staging worked. Two days later the conservative parties all voted with the Nazis in the Reichstag to neuter their own power.

Remarkably, this epochal day, long-relegated to the history books, has once again become a topic of political importance.

Crown Prince Wilhelm’s grandson, Georg Friedrich, the current head of the House of Hohenzollern, is seeking €1.2 million in compensation, plus a collection of art back from the German state, which were taken from his family by the Soviets after the Second World War.

The case has been rumbling on for years. But it gained renewed prominence this summer when the state of Brandenburg appeared to be moving towards cutting an out of court deal with the former royals.

On the face of it, the Hohenzollern have as much right to compensation as thousands of other families who had their property expropriated by the communists after the war. A 1994 law established a legal right to compensation in such cases. But it came with one big caveat: the right to compensation is nixed if the family provided “significant support” to the Nazi dictatorship.

This puts Kaiser Bill’s descendants in a bit of a pickle. The overthrown Kaiser himself notoriously remarked in 1928 that “Jews and mosquitos are a plague that the human race needs to rid itself of. I believe gas would be best.”

His son, Crown Prince Wilhelm, was no better. He was so radical that his father banished him to the outer reaches of his empire before the First World War since he feared he was plotting a coup.

In the early 1930s, when Germany was riven by the chaos brought on by the great Depression, Crown Prince Wilhelm thought he could plot his family’s way back to the throne - and he would stop at nothing to get there, including making deals with the Nazis.

His participation in the Day of Potsdam was perhaps the most significant display of his acquiescence to Nazi rule. But behind the scenes he was equally active. The historian Katrin Urbach has called him one of the “useful idiots” of the German aristocracy who gave Hitler a veneer of respectability.

Other serious historians see it differently. Christopher Clark, a Cambridge historian asked by the Hohenzollern to write an assessment of the Crown Prince’s role, came to the conclusion that the man was “a twit” whom even monarchists didn’t take seriously.

What’s motivating the Hohenzollern family today isn’t quite clear. They still own a castle beloved by tourists in the south of the country and wouldn’t appear to be hard up for cash. And if George Friedrich had hoped to clear his family’s name… resting your case on the argument that your grandfather was a self-delusional nitwit who didn’t take Hitler seriously enough is never a good look.

Meanwhile historians critical of Crown Prince Wilhelm complain that Georg Friedrich’s lawyers have been intimidating them with a barrage of legal threats to the point that some now fear publishing on the topic.

More broadly, the case shows just how ignorant the German public is about the Hohenzollern era. Beyond bemusement that the family think they have a right to be treated like any other landowner, people don’t seem to know what to make of their former royal rulers.

Perhaps it’s time Germany gave more thought to the first five decades of its existence as a modern state. What is history to make of the family under whom Germany rose to become the most advanced industrial nation in the world, but who were responsible for ethnic cleansing in Africa and catastrophic war in Europe?

J.L.

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