Nationalism emerged at the close of the Middle Ages (A.D. c. 450–c. 1500) in Europe. Nationalism is defined as a people's sense that they belong together as a nation because of a shared history and culture, and often because of a common language and/or religion. By the 1700s, several countries, notably England, France, and Spain, had developed as "nation-states," groups of people with a shared background who occupy a land that is governed independently. Nation-states began replacing fiefs (huge estates controlled by noblemen), tribes, city-states, and empires, which overlapped one another as organizing units, dividing peoples' loyalties.
By the 1800s nationalism had become a powerful force, resulting in the idea that any national group has the right to form its own state. Because of this belief, called national self-determination, some nations achieved independence (including Greece, which gained freedom from Turkey in 1829, and Belgium, which won self-rule from the Netherlands in 1830). Others formed new, larger countries. For instance, both Italy and Germany were created by the unification of numerous smaller states—Italy in 1870 and Germany one year later. Still others carved smaller states out of a great empire. The breakup of the Austro-Hungarian Empire following World War I (1914–18) resulted in the formation of the independent countries of Austria, Hungary, Czechoslovakia, Poland, and, later, Yugoslavia.
During the 1800s nationalism in the United States took the form of Manifest Destiny, the mission to expand the country's boundaries to include as much of North America as possible. By the end of the century the United States had claimed all of its present-day territory.
While nationalism is a source of pride and patriotism and has had many positive results, some leaders have carried it to extremes. For example, German dictator (absolute ruler) Adolf Hitler (1889–1945) initiated large-scale movements that resulted in the persecution of "enemies of the state" and in the annihilation of Jews.
The boundary lines that were drawn on the world map at the end of the twentieth century were largely the result of nationalistic movements, some of which had resulted in conflicts. Some of those conflicts remain unresolved.
Further Information: Anthony, Smith, and John Hutchinson, eds. Nationalism. New York: Oxford University Press, 1995; Halsall, Paul, ed. "Nationalism." Internet Modern History Sourcebook. [Online] Available http://www.fordham.edu/halsall/mod/modsbook17.html, November 1, 2000; "Nationalism Links." Sociological Research Online. [Online] Available http://www.socresonline.org.uk/2/1/natlinks.html, November 1, 2000.