Nationalism is a political, social, and economic system characterized by the promotion of the interests of a particular nation, especially with the aim of gaining and maintaining sovereignty (self-governance) over the homeland. The political ideology of nationalism holds that a nation should govern itself, free from outside interference and is linked to the concept of self-determination. Nationalism is further oriented towards developing and maintaining a national identity based on shared, social characteristics, such as culture and language, religion and politics, and a belief in a common ancestry. Nationalism, therefore, seeks to preserve a nation's culture, by way of pride in national achievements, and is closely linked to patriotism, which, in some cases, includes the belief that the nation should control the country's government and the means of production.
Historically, nationalism is a modern concept dating from the 18th century, of an ideological scope greater than a peoples' attachment to family, to local authority, and to the native land. Politically and sociologically, there are three paradigms for understanding the origins and bases of nationalism. The first paradigm is primordialism (perennialism), which proposes nationalism as a natural phenomenon, that nations have always existed. The second paradigm is ethnosymbolism, a complex, historical perspective, which explains nationalism as a dynamic, evolutionary phenomenon imbued with historical meaning, by way of the nation's subjective ties to national symbols. The third paradigm is modernism, which proposes that nationalism is a recent social phenomenon that requires the socio-economic structures of modern society to exist.
There are various definitions for what constitutes a nation, however, which leads to several different strands of nationalism. It can be a belief that citizenship in a state should be limited to one ethnic, cultural, religious, or identity group, or that multinationality in a single state should necessarily comprise the right to express and exercise national identity even by minorities. The adoption of national identity in terms of historical development has commonly been the result of a response by influential groups unsatisfied with traditional identities due to inconsistency between their defined social order and the experience of that social order by its members, resulting in a situation of anomie that nationalists seek to resolve. This anomie results in a society or societies reinterpreting identity, retaining elements that are deemed acceptable and removing elements deemed unacceptable, to create a unified community. This development may be the result of internal structural issues or the result of resentment by an existing group or groups towards other communities, especially foreign powers that are or are deemed to be controlling them.National symbols and flags, national anthems, national languages, national myths and other symbols of national identity are highly important in nationalism.