On 30 April 1945, as the Red Army battled the last remaining fanatical resistance of Nazi Germany in the streets of Berlin and the Second World War in Europe was drawing to a close, Adolf Hitler retired to his private quarters in the Führerbunker one last time. What happened in that room continues to be a source of mystery, controversy and debate 74 years later. Politics is largely to blame.

“Politics? I don’t get involved in politics anymore. I detest politics,” said Hitler from his bunker. And yet, the arch-hypocrite proceeded to dictate a last political testament. Moreover, in choosing to kill himself instead of escaping to his holiday retreat in Obersalzberg, Hitler was hoping to make a final, extreme, political statement.

On 1 May, Großadmiral Karl Dönitz – Hitler’s nominated successor – broadcast a message on Hamburg Radio stating that Hitler had died “at his command post… fighting to the last breath against Bolshevism”. The Allies were understandably concerned by this. The Foreign Office did not want Hitler’s manner of death to become the subject of a myth, and argued almost immediately that Britain “must do all in our power to play it down”. But the Soviet leader, Joseph Stalin, had other ideas. On the same day that Soviet soldiers announced to the world that they had found Hitler’s body and confirmed he had poisoned himself, Stalin was spreading a myth of his own: the idea that Hitler was still alive.

It is very likely that Stalin was playing political games. He knew that the Soviets had found the Führer’s remains when he claimed that Hitler could have escaped to Spain or Argentina. But saying this helped him to undermine his political opponents, and strengthened his hand in territorial disputes. It also allowed him to avoid sharing Soviet evidence with the West, as this would have involved revealing the many embarrassing shortcomings of the “botched” Soviet investigation into Hitler’s last days.

Following the Soviet allegation that Hitler was living in the British Zone of Germany, British intelligence instructed the historian and distinguished intelligence officer, Hugh Trevor-Roper, to find out what really happened to Hitler. Politics played a part in this, too. The British hoped Trevor-Roper’s findings would prevent the spreading of a “Hitler myth”. The Foreign Office even considered destroying copies of Hitler’s wills when they were discovered, lest they inspire a Nazi resurgence.

Trevor-Roper’s evidence-based conclusions, conveyed in his masterful book, The Last Days of Hitler, are still convincing. Hitler shot himself. His new bride, Eva Hitler (née Braun), took cyanide. The future Lord Dacre and his fellow intelligence officers found that tales of Hitler’s escape were disseminated by individuals with dubious motives (neo-Nazism, money making, sensationalism, journalism etc) and with no credible evidence to support their extraordinary claims. The Soviets had nothing much to say about this. For years they maintained an official silence on the issue.

Eventually, in 1968, a Soviet autopsy report on what was claimed to be the corpses of Adolf and Eva was published. The autopsy concluded that Hitler died from cyanide poisoning. Hitler’s survival was no longer the official Soviet line. But determining his method of suicide became entangled in Cold War politics. The Führer’s manner of death was believed to reveal something about his character.

The Soviets insisted that Hitler poisoned himself (a cowardly death, like his dog). Western historians rightly argued that the autopsy was riddled with scientific inconsistencies. But they were accused of defending Hitler by suggesting he had shot himself (a soldier’s death). Others believed he did both.

As the Cold War thawed in the 1990s, Moscow released more of its evidence. This included a piece of skull, damaged by a bullet hole, which several scholars claimed finally proved Hitler had blown his brains out. The mystery was solved.

The skull was DNA tested in 2009 by a team of scientists from the University of Connecticut and found to be female. This unleashed a wave of modern conspiracy theories. Stalin was right, they claimed, Hitler had escaped to Argentina. Trevor-Roper’s investigations were a politically motivated cover-up. Stalin’s political motivations were ignored and the political issues surrounding Trevor-Roper’s investigations taken out of context. The western intelligence services had allowed Hitler to escape!

Of course, one only has to analyse the many intelligence files concerning Hitler’s death to prove such conspiracy theories are nonsense. For example, although political considerations did provide the impetus for the initiation of Trevor-Roper’s investigations, political motivations did not affect the objectivity of the evidence or the conclusions he produced. Trevor-Roper himself argued against Foreign Office attempts to politicise his conclusions, and won. As he told the Joint Intelligence Committee in 1946: “The book is intended as history rather than propaganda; I think the facts are true as given; and I have been more concerned to understand the events and their causes and relations, than to push a point of view.”

Hitler’s last days still influence modern politics. Theresa May has been accused several times by newspapers and politicians, including Jeremy Corbyn, of exhibiting a “bunker mentality”. Just last year, journalists have suggested that Vladimir Putin has a personal interest in Moscow’s Hitler files.

But even though a team of journalists and forensic scientists were permitted to confirm, once again, through forensic analysis, that teeth stored in Moscow belong to Hitler, they were not permitted to carry out a new DNA test on the skull. Perhaps Russia is worried that the tests will again indicate that the skull belongs to a woman and inspire a new generation of conspiracists. Theories of Hitler’s post-war survival are understandably hurtful to many Russian people. But Russia has no cause for concern.

If the skull is DNA tested again and found to be Hitler’s, then it is surely game over for the conspiracy theorists. If it is proven to be female once more, this does not suggest Hitler escaped. Instead, it suggests that the Soviet investigations were more botched than was previously thought. Nothing changes the fact that the Russians decimated the Wehrmacht, inspired Hitler to shoot himself to escape their capture and found all that was left of him buried outside the Führerbunker. We know this, because they, indisputably, have his teeth.

So why do so many people still believe Hitler escaped? As the ideas of modern conspiracy theorists are remarkably similar to those disproved by Anglo-American intelligence in the 1940s and 1950s, it is reasonable to assume that many of them share the same motives as their twentieth-century predecessors. Worryingly, neo-Nazism could still be a motive for some as Holocaust denier David Irving recently described the belief in Hitler’s escape as “wishful thinking”. Since all serious historians are opposed to the poor research methods, distortion of historical facts and the negative consequences produced by “Hitler escaped” publications, I suggest we share a common foe.

There is much talk in newspapers at the moment of a “new Cold War”. However, what is needed now is not a new Cold War but rather a new Grand Alliance of international scholars, Western and Russian, working together, to make the case against conspiracy theories of Hitler’s escape.

Luke Daly-Groves is a historian and author of ‘Hitler's Death: The Case Against Conspiracy’. He is currently studying for his PhD at the University of Leeds.