U.S History. 1877-2008 By hunter.peterson Period: 1776 to 1860 Early American History Period: 1860 to 1877 Civil War / Reconstruction Period: 1877 to 1900 The Gilded Age Period: 1890 to 1920 The Progressive Era Period: 1898 to 1910 Imperialism Period: 1914 to 1918 World War 1 Period: 1920 to 1929 Roaring Twenties Period: 1929 to 1939 Great Depression Period: 1939 to 1945 World War 2 1945 United Nations formed Period: 1945 to 1960 Early Cold War 1948 Berlin Airlift 1949 NATO established 1950 Korean War Period: 1950 to 1970 Civil Rights Era Period: 1950 to 1953 Korean War 1951 Rosenbergs trial Period: 1951 to 1951 Rosenbergs trial 1952 First H-Bomb detonated by the United States Period: 1952 to 1952 First H-Bomb detonated by the United States Period: 1954 to 1976 Vietnam War 1955 Jonas Salk invented the polio vaccine Period: 1955 to 1955 Jonas Salk invented the polio vaccine Period: 1955 to 1956 Bus Boycott and Rosa Park arrested 1957 USSR launches Sputnik 1957 little rock nine Period: 1957 to 1957 USSR launches Sputnik 1961 bay of pigs invasion 1961 Berlin wall made 1962 Cuban Missile Crisis 1963 "I Have A Dream Speech" 1963 JFK killed 1965 medicare and medicaid established 1968 Tet Offensive 1968 MLK killed 1969 first man to the moon Period: 1970 to 1991 End of the Cold War 1971 Pentagon Papers Leaked 1975 The Fall of Saigon, marks end of Vietnam war. Period: 1990 to 2008 1990s-21st Century