A historical anniversary can be something of a false god. Convinced – rightly or wrongly – of the reading public’s numerical obsession, publishers race to churn out their own ‘definitive’ accounts of the event being commemorated. This year has been particularly notable for this, witnessing as it has not only the centenary of the Russian Revolution, but also the quincentenary of the event that supposedly began the Reformation: 31 October will mark the anniversary of Martin Luther nailing to the door of the church attached to Wittenberg Castle his ninety-five theses against papal teaching on indulgences.

Or, at least, so we are told. One of the central claims of Peter Marshall’s lovely 1517: Martin Luther and the Invention of the Reformation is that this event probably never happened. In claiming this, he is following a well-trodden path, as he readily admits: the German Catholic historian Erwin Iserloh already suggested in the early 1960s that the historical evidence for the ‘theses-posting’ (the German, Thesenanschlag, conveys far better the force of the supposed event), which allegedly occurred on All Saints’ Eve 1517, was very dubious. But Marshall also has a new story to tell, one that is concerned with anniversaries and is often far more interesting than the many repetitive accounts of Luther and the Reformation that have appeared this year. That is the story of how the Thesenanschlag gradually came to assume such a central role in European and American cultural memory, generating the modern idea of the ‘Reformation’.

This is a story worth telling, for, as Marshall rightly points out, Luther’s supposed actions continue to permeate much of modern culture. At the serious end of the spectrum one need only mention 10 July 1966, when Martin Luther King Jr – in the words of his widow, Coretta – ‘nailed his demands to the closed door of [Chicago] City Hall, as Martin Luther had nailed his Ninety-Five Theses to the door at Wittenberg’. It was, said Coretta, ‘a magnificent symbolic gesture that rang down the centuries from his namesake’. But the putative theses-posting has also inspired a legion of less serious cultural imitations (my favourite of those mentioned is the tantalisingly titled 2003 book Theses on 95 Sexdecillion Indulgences: With Flirts and Spices).

Marshall’s argument is not that these cultural references are worthless because the Thesenanschlag did not happen. Rather, it is that a ‘cultural history of an imagined event’ can explain much about how societies use the past. He begins with two chapters on the historical reality of what Luther did in late 1517 and how his actions were immediately received. The earliest testimonies for the Thesenanschlag in something like its modern form – albeit with no reference to Luther himself nailing the theses to the door – come from the 1540s. Marshall dissects the evidence concisely. Discussing the unlikeliness of Luther nailing the theses to the door, he notes solemnly: ‘As the historian Daniel Jütte has established, there is considerable evidence that sixteenth-century people more commonly used glue or wax when pasting up placards and notices in public places.’ His tentative conclusion is that Luther never posted the theses on 31 October, only sending them out privately; any posting, if it happened at all, happened later in November.

More important is the broader context. For a late medieval university professor, posting theses for debate was a far from revolutionary act; in fact, it was a typical exercise that would not have attracted the sort of immediate stunned reaction that is central to so many later depictions. Nor was Luther’s attack on indulgences an assault on the whole fabric of the late medieval Church. Rather, it was a response to local debates. Luther’s own position at this point was a cautious one – the pope’s authority was still respected, and he did not challenge the reality of purgatory or the value of good works.

It was only when this high-minded academic critique was disseminated on a scale that no one (not least Luther) could have predicted that it also radicalised into an attack on the papacy tout court. A particularly important moment was the public disputation with Johann Eck in June and July 1519, at which Luther was pressed into admitting that popes were fallible; the final die was cast in December 1520, when Luther burned a papal bull outside Wittenberg’s Elster Gate. Nonetheless, in his later autobiographical writings, Luther continued to present October 1517 as a watershed moment, and in this he was emulated by many of his earliest followers.

However, the same followers still attached greater significance to other episodes. To take only one example, the first full-length Protestant biography (published in 1556), by Ludwig Rabus, included eleven woodcuts depicting scenes from Luther’s life; the Thesenanschlag is conspicuous only by its absence, with events such as the burning of the papal bull given much more prominence. But the idea that 1517 marked the beginning of the Reformation continued to crystallise. Marshall argues that the celebrations of 1617 – at least in Germany – constituted the ‘first large-scale modern centenary’. Commemorative medals were issued and Luther-themed plays staged. And yet, the theses-posting remained a minor theme.

One explanation for the event’s later rise in prominence was the ‘commodification’ of Lutheranism in the new consumer culture of the 18th century. Prints and even silver-gilt beakers serialising Luther’s life now depicted it. But more dramatic scenes continued to appear with greater frequency on the dozens of Luther coins and medals minted in Germany. Some tourists to Wittenberg even preferred to commemorate the tomb of the ‘mild’ Melanchthon more than any site associated with the ‘hot-headed’ Luther (these are the words of Boswell writing to Samuel Johnson in 1764).

It was only in the 19th century that the Thesenanschlag acquired its seminal status. In the wake of the French Revolution and the Napoleonic Wars, the event came to be read less in theological and more in political terms, and Luther’s opposition to indulgences became an emblem for struggle against oppression more generally. In Germany, Luther developed into a symbol of German freedom and nationhood – Herder referred to him as the man who gave a nation asleep ‘under the yoke of foreign words and customs … its authentic speech’. This process should not be confused with secularisation: in Germany, it was used as a nation-building myth for a Kleindeutschland that would exclude Catholic Austria; in the USA, preachers used the 1817 anniversary to contrast American freedom with the ‘gross corruption and spiritual tyranny of Rome’, and even associated 31 October 1517 with 4 July 1776. Travel guides began to highlight the location of the Thesenanschlag (indulging a long cultural tradition, English tourists moaned about conditions in the local hotels). It was at this point that the myth of Luther ‘hammering’ the theses into the church doors became ubiquitous in popular histories. Marshall notes that such hyperbole was actually more common in English and American works than in German ones. Visual representations of the supposed event abounded, from illustrations in children’s books to high art, such as Ferdinand Pauwels’s famous painting for the Reformation room at Wartburg Castle (1871–2).

The Thesenanschlag, in short, became a political symbol of a nebulous ‘liberty’ equally applicable in post-Bismarck monarchical Germany and democratic America. It was such ambiguity, combined with the nationalist overtones that had come to characterise descriptions of it and the rediscovery of Luther’s virulently anti-Semitic works, that allowed it to be easily appropriated by the Nazis. After Pope Pius XI issued an encyclical in 1937 condemning restrictions on Catholics in Germany, Hitler even initially planned a retaliatory speech that ‘would greatly eclipse Luther’s ninety-five theses and … complete the work of the Reformation in the German spirit’. Unsurprisingly, the postwar period saw attempts to find in Lutheranism the ‘roots’ of Germany’s corruption, not least in the immensely popular The Rise and Fall of the Third Reich (1960) by the US war correspondent William L Shirer – a book I remember being set in school in Edinburgh.

Peter Marshall has created a beautiful example of what popular cultural history can be. Rather than telling readers what they already know, or confirming them in their pre-existing political prejudices, he has begun with a well-known ‘fact’ and then used it to tell a new and unfamiliar story. It helps a great deal that, unlike many cultural historians, he eschews jargon in favour of clear and precise prose. Writers of future anniversary histories should take note.