The Treaty of Versailles, signed in June 1919, delineated the terms of peace between the Allies and Germany at the close of World War I. The terms were humiliating and economically devastating for Germany, which had to accept full responsibility for the war, give up part of its territory to the conquering nations, demilitarize, limit its army and navy, and pay an enormous amount in reparations. This embittered the German people, who felt betrayed by the Allied countries.
Adolf Hitler became the head of the National Socialist German Workers Party, or Nazi Party, in 1921. Among key party platforms were the pride of the German people and dissatisfaction with the terms of the Versailles Treaty. After the failed Beer Hall Putsch in Munich in 1923, Hitler began to work within the electoral process to gain power and influence.
The Great Depression, which began in 1929, quickly spread around the world. It hit particularly hard in Germany. Hitler took advantage of the economic upheaval and the desperation of the German people to offer an agenda of German pride and prosperity. As a result, the Nazis captured a significant number of seats in the German Parliament, called the Reichstag. In January of the following year of 1933, Hitler was appointed chancellor of Germany, and the Nazis quickly moved to ban all other political parties and control all facets of German life.
We see, then, that Hitler used the disgruntlement of the German people with the Treaty of Versailles to advance the program of the Nazi Party through propaganda. When the Great Depression caused so much hardship among the German People, they looked for an alternative to the government in power, and Hitler and the Nazi Party were there with promises of glory and prosperity for the German people. Once Hitler had power, he forcibly eliminated opposition, at which point he and the Nazis were free to do whatever they wanted.