Loyalty and devotion to one's nation or country, especially as above loyalty to other groups or to individual interests.
Before the era of the nation-state, the primary allegiance of most people was to their immediate locality or religious group. The rise of large, centralized states weakened local authority, and society's increasing secularization weakened loyalty to religious groups, though shared religion
along with common ethnicity, political heritage, and history
is one of the factors that draws people together in nationalist movements. Early nationalist movements in 18th-and early 19th-century Europe were liberal and internationalist, but they gradually became more conservative and parochial. Nationalism is considered a major contributing cause of World War I, World War II, and many other wars of the modern era. In Africa and Asia in the 20th century, nationalist movements often arose in opposition to colonialism . After the fall of the Soviet Union, powerful nationalist sentiments in eastern Europe and the former Soviet republics contributed to ethnic conflicts, such as those in the territories of the former Yugoslavia.