The Colonial Period: 1647-1776 -- The Pre-Civil War Period: 1777-1860 -- The Civil War and After: 1860-1900 -- Progress and Reform: 1900-1930 -- The Depression and the New Deal: 1930-1940 -- War and Prosperity: 1940-1970 -- Economic and Social Stagnation: 1970-1990 -- Social Welfare and the Information Society: The 1990s