How did America change from 1776 to 1870

America changed drastically because shortly after the revolutionary war they established their first system of government and began electing their own leaders " in this case the president" and over the years expanded West with the Louisiana purchase in 1803 and other territories west of the Mississippi. In 1865 civil war broke out between the north " the union" and the south " the confederacy" over the terms of slavery and president Lincoln created the 13th, 14th, and 15th amendment giving slaves the same right as any American. Shortly after the civil war America began to trade goods with other countries to boost the economy and continued thru the year.