On the night of 30 January 1933, Adolf Hitler leaned out of a spotlit window of the Reich Chancellery in Berlin, bursting with joy. The moment seemed unbelievable, even to Hitler. After an improbable political journey that came close to faltering on many occasions, his march to power had finally succeeded.

While the story of Hitler's rise has been told in books covering larger portions of his life, no previous work has focused on his eight-year climb to rule: 1925–1933. Renowned author Peter Ross Range brings this period back to startling life with a narrative history that describes brushes with power, quests for revenge, nonstop electioneering and underhand campaign tactics. For Hitler, moments of gloating triumph were followed by abject humiliation.

This is the tale of a school dropout's climb from the infamy of a failed coup to Germany's highest office. It is a saga of personal growth and lavish living, a melodrama rife with love affairs and even suicide attempts. But it is also the definitive account of Hitler's unrelenting struggle for control over his raucous movement as he fought off challenges, built and bullied coalitions, quelled internecine feuds and neutralised his enemies – all culminating in the creation of the Third Reich and the world's descent into darkness.

One of the most dramatic and important stories of the twentieth century, Hitler's ascent spans Germany's wobbly recovery from the First World War through years of growing prosperity and, finally, into crippling depression. Masterfully woven into an unforgettable and urgent narrative, The Unfathomable Ascent will remind us of what we should never forget.