The main causes of World War I were Mutual Defense Alliances, Imperialism, Militarism, Nationalism, and the assassination of Archduke Franz Ferdinand.
Answer:
Early humans migrated to America crossing the Bering Strait, which back then was a wide swath of land, about 15,000 years ago.
The fascist leaders in Italy came to power in the 1920s and 1930s because they supported the League of Nations.