Nationalism is an ideology that emphasizes loyalty, devotion, or allegiance to a nation or nation-state and holds that such obligations outweigh other individual or group interests.

Nationalism is a powerful force in the world but it is difficult to arrive at agreement regarding the definition of terms like nation or nationalism. Nationalism has emerged as one of the most compelling political creeds which has helped to shape history, During the last two centuries or more. 

• United people as well as divided them: It helped to liberate them from oppressive rule as well as been the cause of conflict and bitterness and wars

Phases of Nationalism:

• Phases of Nationalism led to the unification of various little realms into bigger country states, in nineteenth century Europe. For example, the current day Italian and German states
• Latin America established countless new states. Nearby loyalties were additionally progressively solidified into state loyalties and normal dialects, alongside the union of state limits, nearby vernaculars
• membership of the nation-state was based on the people of the new states acquiring a new political identity
• Similar process of consolidation has taken place in India in the last century or more

Contributed to the Break-Up of Large Empires: Such as the Russian empire and  Austro-Hungarian in the early twentieth century in Europe as well as the break-up of the Dutch, British, French, and Portuguese empires in Africa and Asia

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Redrawing State Boundaries:

• • Starting around 1960, even obviously stable country states have been stood up to by patriot requests set forward by gatherings or regions which include demands for separate statehood 
  • Today, in many parts of the world there are nationalist struggles that threaten to divide existing states. Such as, the Kurds in Turkey, the Basques in northern Spain, the Quebecois in Canada and Iraq and the Tamils in Sri Lanka
  •  In a pan Arab union, Arab nationalism today may hope to unite Arab countries

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Nations and Nationalism:

• Nations and Nationalism is commonly believed that nations are constituted by a group who share certain features such as descent, or language, or religion or ethnicity
• Many nations do not have a common language or common religion such as India has a large number of languages which are spoken in different regions and by different communities
• Nation Forming Diverse Groups of Society:
• Different from the family: Which is based on face-to-face relationships with each member having direct personal knowledge of the character of others and the identity
• Different from tribes and clans and other kinship groups: Ties of marriage and descent link members to each other so that even if one does not personally know all the members one can trace the links that bind them
• As a member of a nation: People may never come face to face with most of our fellow nationals nor need to share ties of descent with them. Yet nations exist, valued by their members and are lived in

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Incorporating Nation: 

• A nation is to a great extent an ‘imagined’ community, held together by the collective beliefs, and imaginations of incorporating nation members

Incorporating Nation is based on certain assumptions which people make about the collective whole with which they identify

Conclusion

In the last two centuries, nationalism has emerged as the most powerful political force to shape the history of countries. It takes centuries to build a nation but only a few years to destroy it and it is the feeling of nationalism that binds the country and its people in one thread of Unity. To build a nation people have a sense of belongingness and belief. They must have a common history and most importantly; they must have a shared political ideals. Common political thoughts is the most important factor. For example, one community believes in  autocracy and the other community believes in democracy, they  never share a feeling of belongingness and sense of unity. Nationalism can be based on religion, race, pride, anger or any emotional  factor which is present in the socio-cultural environment of a nation.