The emergence of nation-states in Europe left a deep impact on the future course of world history. In fact thereafter the history of world is nothing but the history of free nation-states. The ruler of these states accorded top priority to their national interests and tried to safeguard the same through all possible methods.

The rise of nation-states also pro­moted feeling of nationalism and patriotism among the people and at times proved to be a vital cause for rivalry amongst various powers. This rivalry either took the shape of contest for colonies or trade concessions in Asia, America and elsewhere. At times the rivalries grew so acute that they resulted in long drawn wars between various powers and caused enormous loss of men and money.