  the military history of the united states spans a period of over two centuries. during those years, the united states evolved from a new nation fighting great britain for independence (1775â1783), through the monumental american civil war (1861â65) to the world's sole remaining superpower of the late 20th century and early 21st century.john whiteclay chambers, ed., the oxford guide to american military history (1999) ==overview==   the continental congress in 1775 established the continental army and named general george washington its commander. this newly formed army, along with state militia forces, and the french army and navy, defeated the british in 1781. the new constitution in 1789 made the president the commander in chief, with authority for the congress to levy taxes, make the laws, and declare war.jeremy black, america as a military power: from the american revolution to the c
Military_history_of_the_United_States