The Italian American (Italian: italoamericani [ italo.ameri ka ni]) ethnic group comprises Americans who have full or partial ancestry from Italy, especially those who identify with that ancestry, along with their cultural characteristics. Italian Americans are the fourth largest European ethnic group in the United States (not including American ethnicity, an ethnonym used by many in the United States; overall, Italian Americans rank seventh, behind German American, Irish American, African American, English American, American, and Mexican American). About 5.5 million Italians immigrated to the United States from 1820 to 2004. Immigration began in earnest during the 1870s, when more than twice as many Italians immigrated (1870-79: 46,296) than during the five previous decades altogether (1820-69: 22,627). The 1870s were followed by the greatest surge of immigration, which occurred in the period between 1880 and 1920 and brought more than 4 million Italians to America. About 84% of the Italian immigrants came from Southern Italy and Sicily. These were largely agricultural and overpopulated regions, where much of the populace had been impoverished by centuries of foreign misrule, and the economic measures (an oppressive taxation system) imposed on the South after the Italian unification in 1861. After unification, the Italian government initially encouraged emigration to relieve economic pressures in the South. After the American Civil War, which resulted in over a half million killed or wounded, immigrant workers were recruited from Italy and elsewhere to fill the labor shortage caused by the war. In the United States, most Italians began their new lives as manual laborers in Eastern cities, mining camps and in agriculture. Italian Americans gradually moved from the lower rungs of the economic scale in the first generation (1890s 1920s) to a level comparable to the national average by 1970. By 1990, more than 65% of Italian Americans were managerial, professional, or white-collar workers. The Italian-American communities have often been characterized by strong ties with family, the Catholic Church, fraternal organizations and political parties. Today, over 17 million Americans claim Italian ancestry, third only to Brazil with 31 million, and Argentina, which has 24 million people with Italian roots. Italians and their descendents in America helped shape the country, and were in turn shaped by it. They have gained prominence in politics, sports, the media, the fine arts, the culinary arts, and numerous other fields of endeavor. Italy is considered a birthplace of theWestern civilization and a cultural superpower. Italy has been the starting point of phenomena of international impact such as the Roman Empire, the Roman Catholic Church, the Renaissance and theRisorgimento. During its history, the nation gave birth to an enormous number of notable people. Both the internal and external facets of Western culture were born on the Italian peninsula, whether one looks at the history of the Christian faith, civil institutions (such as the Senate), philosophy, law, art, science, or social customs and culture. Italy was home to many well-known and influential civilizations, including theEtruscans, Samnites, Phoenicians, Greeks, and the Romans. Etruscan and Samnite cultures flourished in Italy before the emergence of the Roman Empire, which conquered and incorporated them. Phoenicians and Greeks established settlements in Italy beginning several centuries before the birth of Christ, and the Greek settlements in particular developed into thriving classical civilizations. The Greek ruins in southern Italy are perhaps the most spectacular and best preserved anywhere. For more than 2,000 years Italy experienced migrations, invasions and was divided into many independent states until 1861 when it became a nation-state.