The 2000 U.S. Census reported 1.2 million people who claimed ancestry in the Arab world. This figure has doubled since 1980, when the census reported 610,000 Arab Americans. In 1990 it reported 860,000. According to the census, Arab Americans represented 4.2 percent of the U.S. population in 2000, but many researchers believe the count is inaccurate and has missed a significant number of Arab Americans. Some researchers and experts place the population at more than 3.5 million. The dramatic rise in population of the Arab Americans is due mainly to high rates of immigration over the last three decades.

The Arab world refers to twenty-one Arab countries. These countries cover vast territories extending from the African shores of the Atlantic Ocean to the Arab-Persian Gulf in Asia. The Arab countries are members of the League of Arab States, also known as the Arab League, which was founded in 1945 to strengthen...