Economic studies have indicated that just as the downturn was spread worldwide by the rigidities of the Gold Standard, it was suspending gold convertibility (or devaluing the currency in gold terms) that did most to make recovery possible. What policies countries followed after casting off the gold standard, and what results followed varied widely.

Every major currency left the gold standard during the Great Depression. Great Britain was the first to do so. Facing speculative attacks on the pound and depleting gold reserves, in September 1931 the Bank of England ceased exchanging pound notes for gold and the pound was floated on foreign exchange markets.

Great Britain, Japan, and the Scandinavian countries left the gold standard in 1931. Other countries, such as Italy and the U.S., remained on the gold standard into 1932 or 1933, while a few countries in the so-called "gold bloc", led by France and including Poland, Belgium and Switzerland, stayed on the standard until 1935–1936.

According to later analysis, the earliness with which a country left the gold standard reliably predicted its economic recovery. For example, Great Britain and Scandinavia, which left the gold standard in 1931, recovered much earlier than France and Belgium, which remained on gold much longer. Countries such as China, which had a silver standard, almost avoided the depression entirely. The connection between leaving the gold standard as a strong predictor of that country's severity of its depression and the length of time of its recovery has been shown to be consistent for dozens of countries, including developing countries. This partly explains why the experience and length of the depression differed between national economies.

The common view among economic historians is that the Great Depression ended with the advent of World War II. Many economists believe that government spending on the war caused or at least accelerated recovery from the Great Depression. However, some consider that it did not play a very large role in the recovery, although it did help in reducing unemployment.

The massive rearmament policies leading up to World War II helped stimulate the economies of Europe in 1937–39. By 1937, unemployment in Britain had fallen to 1.5 million. The mobilization of manpower following the outbreak of war in 1939 finally ended unemployment.

America's entry into the war in 1941 finally eliminated the last effects from the Great Depression and brought the unemployment rate down below 10%. In the U.S., massive war spending doubled economic growth rates, either masking the effects of the Depression or essentially ending the Depression. Businessmen ignored the mounting national debt and heavy new taxes, redoubling their efforts for greater output to take advantage of generous government contracts.

The majority of countries set up relief programs, and most underwent some sort of political upheaval, pushing them to the left or right. In some states, the desperate citizens turned toward nationalist demagogues—the most infamous being Adolf Hitler—setting the stage for World War II in 1939.

Australia's extreme dependence on agricultural and industrial exports meant it was one of the hardest-hit countries in the Western world. Falling export demand and commodity prices placed massive downward pressures on wages. Further, unemployment reached a record high of 29% in 1932, with incidents of civil unrest becoming common. After 1932, an increase in wool and meat prices led to a gradual recovery.