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He walked with a peculiar gait, lurching from side to side in the narrow corridors as though looking for support from the walls of the bunker. His face was pasty and bloated, his eyes bloodshot. He could scarcely read, even though all papers were typed out for him in letters three times the normal size on special “Führer typewriters”. There was a bad tremor in his left hand. His clothes, which had always been so spick and span, were now spattered with food stains. He would lie on the sofa for hours munching slice after slice of cake, talking of nothing but dogs and dog training, the dangers of eating meat and, of course, how everyone had betrayed him — Goering, Himmler, Speer, the German people — everyone except Eva Braun (shortly and so briefly to become Frau Hitler) and Blondi his alsatian.

The bunker was a horrible place. Although it had 20 rooms, nearer 50 if you include the outer bunker above, they were all small and sparsely furnished, with naked light bulbs casting a cold light from the ceiling. Oily puddles collected in the corridors. In the final days, there was a terrible stench of diesel fumes, sweat and urine — although, as ever, Hitler insisted on a strict no-smoking policy. Even Goebbels tried to avoid the Führerbunker because of the desolate mood that infected its inhabitants. In the streets outside, dozens of corpses swung from trees and lampposts, left over from the wave of executions in March. Ever since February, thousands of Berliners had been killing themselves each month, driven to suicide by the approaching end of the Reich that was to last 1,000 years.

There was one exception to this unmitigated despair. Adolf Hitler himself was, no, not happy (of true happiness he was incapable), but he was at ease with himself. This was where he belonged and, when urged to fly south to make his final stand, he had little difficulty in deciding to stay put. “The Führer must not die in a summerhouse,” as Goebbels put it, on message to the last.

Hitler was, after all, a creature of the underground. After seeing him at work in one of his concrete burrows, Claus Schenk von Stauffenberg, the nearly assassin of July 20, 1944, exclaimed, “Hitler in the bunker — that’s the real Hitler.” Albert Speer recorded that as early as 1933, when they were discussing their grandiose architectural plans for the new Reich, “Hitler kept drawing bunkers, again and again bunkers”.

Joachim Fest, in his unputdownable account of those last worst days, points out how little pleasure Hitler had taken in his blitzkrieg victories. Even in February 1941 he was worried about the prospects of a peace with Russia and was already planning to attack Afghanistan and India. His initial programme was, in German terms, quite orthodox. As far back as 1926 the German army had plans to liberate the Rhineland, eliminate the Polish Corridor and annex Austria. What was, as Fest puts it, “a break with everything the world had ever stood for” was the limitless nihilism, the unquenchable thirst for destruction that was to include the German people as well as their enemies. The Nero Command of March 1945 had ordered the territory of the Reich to be turned into a desert void of civilisation. The war was to be fought without thought of the civilian population.

Hitler wanted to be celebrated not as another Alexander or Napoleon but as an Alaric, Attila or Genghis Khan, the last and greatest of barbarian destroyers. Looking back, his only regret was that he had been too indecisive, too half-hearted, too benign, except, he was proud to record, he had cleansed “the German lebensraum of the Jewish poison” — so much for those who have tried to invent a “moderate” Hitler egged on by extremists.

Fest’s account nearly 60 years on brings back the full horror as though it were yesterday, though it lacks the majestic sweep and caustic wit of Hugh Trevor-Roper’s The Last Days of Hitler, which was written in the months immediately after on the basis of interviews with survivors and remains an imperishable masterpiece to be compared with Gibbon or Macaulay. Inside Hitler’s Bunker also necessarily repeats a good deal of the material in the last two chapters of Fest’s memorable life of Hitler, the first great German biography of their evil genius.

For all their ingenious efforts, neither Fest nor Trevor-Roper can explain how this passion for destruction took hold of the nation of Goethe and Schubert, but then nor can anyone else. To locate the poison somewhere deep in the German soul, as both writers do, is surely a dangerous business, for Pol Pot and others have shown us that this terrible intoxication is not unique to Germans. And as we now know, Hitler is not the only person to have been thrilled by “the thought of the devastating effects a bomb or rocket attack would have on the canyons of Manhattan”.

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