Why did the Depression make the League's job more difficult?

An increased number of people began supporting extremist parties, such as the Nazis, as a result of the unemployment and suffering caused by the depression. This is because they promised to solve the economic problems in their respective countries and had good plans of doing so.

The world's leading economic power, the United States, was the hardest hit by the depression, and it resulted in loans to countries abroad being recalled, such as the loans to Germany as secured under the Dawes Plan.

International Trade and cooperation declined as countries tried to encourage people to buy goods produced locally by introducing tariffs on international imports.

The US focused on it's internal problems and look little interest in Europe's problems as it developed a policy of isolationism.

The League was unable to use economic sanctions to effectively punish aggressive countries as countries feared the sanctions would further damage their economies. 

During the depression, the main leading countries of the League, Britain and France, suffered heavily, so they were reluctant to stand up to dictators as they were busy dealing with internal problems resulting from the depression.

Many countries became nationalist and began to expand their military and empire. They began invading other countries to secure natural resources which they believed would help them to recover from the depression.