What was the most important factor in Hitler's rise to power and why?
In my view, the most important factor in Hitler’s rise to power was German unhappiness with the Weimar Republic and its failure to provide the strong and prosperous country that they wanted.
After WWI, the German monarchy came to an end and a republic was created. This government is now known as the Weimar Republic. The Weimar Republic had many troubles. It was unable to maintain order very well within the country. It was unable to assert itself in foreign affairs. Finally, it was unable to keep Germany’s economy strong. All of these things made Germans very angry and led them to support radical parties like the Nazis.
After WWI, the Allies imposed harsh terms on Germany in the Treaty of Versailles. They deprived Germany of the right to have a major military. They took away German territory. They forced Germany to admit guilt for the war and to pay heavy reparations to the Allies. All of these things angered Germans and they were unhappy with the Weimar Republic because it could not force the Allies to soften these terms.
In part because of the reparations, and then because of the Great Depression, the German economy was very weak by the early 1930s. There was terrible hyperinflation that made money worthless and drained people’s confidence. Germans were naturally displeased with their government for failing to fix the economy.
Because of these things, there was a great deal of political unrest in Germany in these years. Radical parties on the left and the right arose. There were attempted coups and street fighting. Conditions seemed to be deteriorating and the Weimar government could not reverse the trend.
All of these things made Germans unhappy with the Weimar Republic. They wanted someone to fix the problems that the Republic could not. Hitler and the Nazis seemed to have a clear plan to solve these issues and return Germany to power and prosperity. This, I would argue, was the main factor that allowed Hitler to become Chancellor in 1933.