How did postwar conditions (after ww1) contribute to a rise in dictatorships in europe?

They were all in the depression at the time. Let's use Hitler and Germany as an example; at the time Hitler was a mere politician and people of Germany wanted to get out of this depression, Hitler announced that he would make Germany the great empire it was by getting themselves out of the depression, and he did! People looked for a government that could help them, or simply someone who could make the country fall out of the depression.

The answer is crop yield.