The Great depression of 1929 affected not only the USA but the whole world. In fact, Germany was said to be the most affected by this horrific experience. The effects of the great depression lead from economic to political affairs, destroying the strength of many of Germany's aspects.
Before the depression itself, Germany had many up leading background problems. After WWI had finished, Germany was faced with the signing of the Treaty of Versailles. Germany was forced to follow many orders and restrictions, which marginalised the country to its superior "allies." The Treaty of Versailles enforced reparations on Germany, as well as loss of land ownership. Just as much as Germany had to pay reparations to its allies, the loss of land also meant loss of industries, mines, etc. which also meant loss of money. Not only a great loss of wealth but also a great loss of resources.
A major factor of the Treaty of Versailles was the conducting of creating Germany as a democracy, or as society likes to account as "dictated peace." This put Germany in a very vulnerable position, as they had never been a democracy before and this weakened the government. Other underlying problems such as hyperinflation and occupations of the Ruhr also contributed to an unstable government in Germany at the time. These background issues assisted in the devastating effects of the Great Depression.
As hyperinflation occurred, plans were introduced to decrease the issue as well as increase production. Streseman introduced the Dawes plan in 1924 to assist Germany in its issues, loaning 800 million Deutsch marks from the USA. This solved Germany's problem for a while however when the Wall Street Crash occurred, Germany was in for a surprise.
As soon as the Wall Street Crash occurred in the USA, Germany was dumb-founded. Already being low on money owing reparations and decreasing economical and political strength, increased the chances of the Great Depression affecting Germany further.