1920s: Big game hunting in African and South American countries is popular with wealthy Europeans and Americans. In 1909, Theodore Roosevelt and his son kill 512 animals on an African safari.

Today: Most big game hunting in Africa and South America is illegal due to dwindling animal populations. The number of tourists visiting these areas, however, has reached record highs.

1920s: American foreign policy favors intervention in the governmental affairs of Caribbean nations.

Today: Despite decades of economic embargoes and other tactics on the part of the United States, Cuba remains controlled by Fidel Castro's communist forces. The United States regularly restricts refugees from Cuba and other poverty-stricken and unstable countries from entering the United States.

1920s: The Soviet Union, led by Vladimir Lenin, is established in the aftermath of the Russian Civil War. Private ownership of property and Christianity are banned, and the Cossacks military...