The syllabus of USA History spans from 1492 (discovery of American Continent) to the current Government of BH Obama. But I am delineating the course for your ease.

1- Colonization period (Spain, France, UK) With special reference to UK's colonies. (This portion is really imp for objective)

2- American revolution (War of Independence) - Causes of war, Declaration of independence, Articles of Confedration, Socio- economic significance of American revolution, Making the constitution, Its salient features

3- Federalist Regime (Not really imp but give it a go to have proper understanding of political structure of US)

4- Democratic-Republican Regime (Some of questions very frequently asked from this portion are Jefferson's democracy, war of 1812 and Monroe Doctrine)

5- Jacksonian Democracy Its characteristics and comparison or contrast with Jeffersonian Democracy

6- American Civil War: causes, foreign policy of US during Civil war, socio-economic significance wih special reference to Industrialization

7- First World war: how USA plunged into it, Wilson's Fourteen Points, Treaty of Versailles, USA's rejection of treaty and Its implications on world peace

8- The great depression causes and impacts

9- Note on President FD Roosevelt (appears once in every 2 exams almost)

10- 2nd World war US entry into war after attempted neutrality, conventions and charters at the end of war, emergence of US and USSR as undisputed powers and start of cold war

11- Cold war, Truman Doctrine, Marshall Plan

12- Short notes on Watergate scandal, Bush Doctrine etc

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"And how can man die better than facing fearful odds, for the ashes of his fathers, and the temples of his Gods?"