What took place in Germany between 1933 and 1945 is not a subject that lacks historical study. Books about the Third Reich, Hitler, nazism and the Holocaust continue to be produced on an industrial scale. And rare is the TV schedule that doesn’t include at least one documentary devoted to one of the above. Beyond that, the period remains the ultimate moral touchstone for any number of contemporary political debates.

But if there is one element of that era that has been relatively neglected, it is, for obvious reasons, the suffering of the German people. In recent years there has been a movement among some German historians to redress the balance and, if not exactly portray the Germans as victims, show the scale of immiseration they endured in the final stages of the war.

It’s delicate work that can easily look like a form of whitewashing. In Promise Me You’ll Shoot Yourself, Florian Huber, a German writer and documentary-maker, tells the story of the mass suicides that broke out, particularly in eastern Germany, as the Soviet forces pushed towards Berlin. Terrified by Joseph Goebbels’s anti-Soviet and anti-Slav propaganda, Germans killed themselves in their “tens of thousands”. “The epidemic,” writes Huber, “was an extreme expression of the meaninglessness and pain people felt in the face of defeat, humiliation, loss, shame, personal suffering and rape.”

The victorious Soviet troops did indeed exact retribution for the savagery their own people had endured with a remorseless campaign of rape. It’s been estimated that up to 2 million German women were raped. So the fear that accompanied Soviet occupation was not unwarranted.

But as dreadful as that assault on women was, something else was going on, a kind of mass existential crisis. In many respects, Germans, particularly women and older men, had been protected from the reality of the Nazis’ total war. The horrors committed on the eastern front, and even the erasure of Germany’s Jews, were covered in euphemistic language that enabled those not directly involved to create their own fictional reality. When that collapsed, the option for believers was often denial or death. The title of the book comes from one of the countless exchanges recorded in the personal diaries Huber draws on to tell this bleak story. “Promise me you’ll shoot yourself when the Russians come,” a father demands of his 21-year-old daughter, handing her his pistol before going off to fight one of the doomed final battles, “otherwise I won’t have another moment’s peace.”

In the small town of Demmin, population 15,000, as many as 700 Germans killed themselves before and after the Russians arrived. They did so through a variety of means: taking poison, jumping into rivers, hanging themselves, slitting wrists, shooting themselves and their loved ones. While these suicides took place all over Germany, they were disproportionately concentrated in the east, which the Red Army occupied. If they could, Germans escaped to the west and the comparatively benign occupation of the Americans, British and French. But defeat at the hands of the Soviets seemed to represent the absolute negation of nazism, the obliteration of the Nazi fantasy; though viewed through another lens, it was the replacement of one totalitarianism with another.

The suicide that presaged the thousands to come was, of course, that of Adolf Hitler. The radio announcement that the Führer had ended his life was meant to convey a courageous refusal to surrender. But in the event, as Huber shows, it served only to rob many millions of Germans of a sense of purpose.

There was no great outbreak of mourning when the news broke that Hitler, the man who’d driven his country to destruction, was dead. “In almost all German memoirs that describe this period,” Huber writes, “his death is a gaping void.”

For those who’d believed in ultra-nationalism and racial superiority, there was nowhere emotionally or intellectually to go. That said, it was middle-ranking Nazis who proved most adept at slipping away rather than slitting their own throats.

Huber retells the self-annihilation of May 1945 in dispassionate, vivid detail, but after a while the sheer repetition of “ordinary Germans” ending their lives begins to dull the senses. At around about halfway through the book, he shifts the narrative back to the early days of optimism, when Hitler first came to power. It’s a rather jarring turn in direction that revisits some well-trodden ground, although Huber seeks to find new paths by using the recollections of some of the diarists he introduces earlier in the book. But little new light is shed on what we already know.

Nonetheless, reading the testaments of people who’d come through a period of great uncertainty in the late 1920s and early 1930s, with the liberal order seemingly spent, it’s hard not to hear faint echoes in our current plight. As they do now, people then craved simple, emotional answers to complex economic and political problems.

In adopting Hitler as their saviour, the Germans were complicit in the greatest crime of the 20th century. That so few chose to acknowledge it must surely have contributed to the suicidal reckoning that many thousands made at the end of the war.

• Promise Me You’ll Shoot Yourself by Florian Huber is published by Allen Lane (£20). To order a copy go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99

• In the UK, Samaritans can be contacted on 116 123. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is 13 11 14. Other international suicide helplines can be found at befrienders.org