1901 Louis Armstrong is born.
1902 The first teddy bear, named for President Roosevelt, is sold in a New York toy store. http://www.whitehouse.gov/history/presidents/tr26.html
1903 W.E.B. DuBois publishes The Souls of Black Folk
1904 Ice cream cones are introduced at the St. Louis World's Fair.
1905 Albert Einstein proposes the theory of relativity. http://www.pbs.org/wgbh/nova/einstein/
1906 Theodore Roosevelt wins the Nobel Peace Prize. http://www.nobel.se/
1907 Oklahoma enters the union as the 46th state.
1908 The newest division of the Department of Justice, the Federal Bureau of Investigation, is formed.
1909 The National Negro Committee, later renamed the NAACP, is established in New York. http://www.naacp.org/
1910 Russian novelist Leo Tolstoy, author of War and Peace, dies. http://www.ltolstoy.com/
1911 The song Alexander's Ragtime Band, by Irving Berlin, popularizes ragtime for mass audiences. http://www.kcmetro.cc.mo.us/pennvalley/biology/lewis/crosby/berlin.htm
1912 The Titanic sinks in the North Atlantic, claiming the lives of over half its passengers.
1913 The first personal income tax is imposed in the U.S. by the Sixteenth Amendment.
1914 World War I begins in Europe.
1915 A German U-Boat sinks the S.S. Lusitania, a British passenger liner.
1916 Jeannette Rankin becomes the first female elected to Congress.
1917 Puerto Rico is declared a U.S. Territory by the Jones Act, granting citizenship to Puerto Ricans.
1918 Jazz becomes an international phenomenon with the Original Dixieland Jazz Band's European tour.
1919 The signing of the Treaty of Versailles ends World War I.
1920 The 19th Amendment gives women the right to vote; the League of Women Voters is established.
1921 Franklin Delano Roosevelt contracts polio, leaving him with only partial usage of his legs.
1922 The Lincoln Memorial is opened to the public in Washington, D.C. http://www.nps.gov/linc/
1923 U.S. President Warren G. Harding dies and is succeeded by Calvin Coolidge.
1924 George Gershwin produces the musical Lady Be Good, starring Fred Astaire. http://www.gershwinfan.com/gershbio.html
1925 F. Scott Fitzgerald writes The Great Gatsby. http://www.sc.edu/fitzgerald/
1926 Langston Hughes, a major leader of the Harlem Renaissance, writes The Weary Blues. http://www.poets.org/poets/poets.cfm?prmID=84
1927 The Jazz Singer debuts as one of the first motion pictures with sound. http://www.filmsite.org/jazz.html
1928 Herbert Hoover is elected president.
1929 The biggest stock market crash to date marks the beginning of the Great Depression.
1930 Astronomers discover Pluto, the ninth and smallest planet.
1931 Spanish surrealist Salvador Dali paints The Persistence of Memory, with its infamous melted clocks. http://www.salvadordalimuseum.org/cgi-bin/SoftCart.exe/index.html?E+dali
1932 The Lindbergh baby, son of the first transatlantic aviator Charles Lindbergh, is kidnapped and killed.
1933 The 14-year Prohibition is repealed by the 21st Amendment.
1934 The Dust Bowl blows topsoil from farmlands, ruining families already destitute from the Depression.
1935 The Asian country Persia is now officially renamed Iran.
1936 One-third of families in the U.S. have total incomes below the poverty line.
1937 Amelia Earhart, the first woman to fly across the Atlantic Ocean, disappears while flying around the world. http://www.nasm.edu/nasm/aero/women_aviators/amelia_earhart.htm
1938 Orson Welles' radio broadcast of War of the Worlds causes national panic and fear of alien invasions. http://www.transparencynow.com/welles.htm
1939 World War II begins in Europe when Britain and France declare war on Germany.
1940 Frank Sinatra joins the Tommy Dorsey Band and rises in popularity.
1941 Japanese forces attack Pearl Harbor, HI, on December 7, "a date which will live in infamy."
1942 Casablanca wins the Academy Award for Best Picture in Hollywood's Golden Age.
1943 The Pentagon, the world's largest office building and the U.S. Department of Defense, is completed.
1944 The Allies invade the beaches at Normandy on June 6, known as D-day.
1945 World War II ends, and Franklin Delano Roosevelt dies in suddenly his fourth term in office.
1946 Dr. Benjamin Spock publishes The Commonsense Book of Baby and Child Care.
1947 Jackie Robinson becomes the first black professional baseball player. http://memory.loc.gov/ammem/jrhtml/jrhome.html
1948 Racial segregation in the U.S. Military is abolished by President Truman.
1949 African-American poet Gwendolyn Brooks wins the Pulitzer Prize for her collection of poetry, "Annie Allen."
1950 Korean War begins when North Korea invades South Korea; U.S. troops are sent to aid South Korea.
1951 Marlon Brando, a relatively unknown young actor, jumpstarts his career in A Streetcar Named Desire.
1952 The first episode of American Bandstand is hosted by Dick Clark.
1953 Twenty million American households have television sets.
1954 Supreme Court ruling on Brown v. Board of Education ends tolerance of racial segregation.
1955 America's first theme park, Disneyland, opens in Southern California.
1956 Martin Luther King organizes a bus boycott in Montgomery, Alabama. http://www.lifemag.com/Life/mlk/mlkpics.html
1957 Sputnik I, launched by the U.S.S.R., is the first satellite to be released into space.
1958 The National Aeronautics and Space Administration (NASA) is established in the U.S. http://www.nasa.gov/
1959 The great modern jazz singer, Billie Holiday, dies. http://www.cmgww.com/music/holiday/
1960 Students "sit in" at southern lunch counters in protest of segregation. http://www.greensboro.com/sitins/stories/main1960.htm
1961 The Berlin Wall is built to stop East Berlin refugees from entering West Berlin.
1962 John Glenn, a Marine Corps pilot, is the first American to orbit the earth.
1963 President John F. Kennedy is assassinated.
1964 The Civil Rights Bill, ordering an end to discrimination, is passed. http://www.eeoc.gov/laws/vii.html
1965 American troops are installed in Vietnam and a full-scale offensive is begun.
1966 The first endangered species list is written by the U.S. Department of the Interior.
1967 Thurgood Marshall is the first black man to become a Justice of the Supreme Court.
1968 Martin Luther King, Jr. is assassinated in Memphis, Tennessee. http://www.lifemag.com/Life/mlk/mlkpics.html
1969 Apollo 11 astronauts become the first men to walk on the moon.
1970 The first New York Marathon takes place in Central Park with 126 entered runners.
1971 John F. Kennedy Center for the Performing Arts opens as a living presidential memorial. http://kennedy-center.org
1972 Five men are arrested in Democratic Headquarters, galvanizing the notorious Watergate scandal.
1973 American troops withdraw from the Vietnam conflict.
1974

Richard Nixon resigns from President of the United States in order to avoid impeachment;

Louis Armstrong dies on July 6, 1971.
1975 Elton John's "Philadelphia Freedom" and Glen Campbell's "Rhinestone Cowboy" top the charts.
1976 Jimmy Carter is elected President, beating incumbent Gerald Ford.
1977 George Lucas's science fiction classic Star Wars hits the box office.
1978 In Jonestown, Guyana, 900 cult followers of Jim Jones commit suicide and murder a Congressman.
1979 Dallas, Three's Company, and The Dukes of Hazzard are some of the most popular television shows.
1980 Mount St. Helen's erupts in Washington, killing 65 people and spewing lava 60,000 feet in the air.
1981 Sandra Day O'Connor becomes the first woman appointed to a Supreme Court position.
1982 The Vietnam War Memorial opens in Washington, D.C., bearing the names of soldiers lost or killed. http://www.nps.gov/vive/index.htm
1983 President Reagan deploys U.S. troops to Grenada to contest a military coup and restore democratic rule.
1984 Former Hollywood actor Ronald Reagan is re-elected President of the United States.
1985 Back to the Future is released, later becoming one of the top-grossing films of all time.
1986 The space shuttle Challenger explodes soon after liftoff, inspiring nationwide mourning for its crew.
1987 President Reagan and Soviet Secretary Gorbachev sign the INF treaty to reduce nuclear stockpiles.
1988 Republican Vice President George Bush wins the Presidential election.
1989 The Berlin Wall, which separated East and West Berlin for 28 years, is torn down.
1990 The space shuttle Discovery, bearing the Hubble Space Telescope, is launched in Florida.
1991 The Persian Gulf War begins after a 1990 invasion of Kuwait by Iraq leads to U.S. bombing in both countries.
1992 Riots ensue in Los Angeles following the policemen's acquittal for beating Rodney King.
1993 The "Don't Ask, Don't Tell" policy is implemented by President Clinton for gays in the military.
1994 Former first lady Jacqueline Kennedy Onassis dies of lymphoma cancer.
1995 A Federal building bombing in Oklahoma City kills 168 people, prompting national mourning.
1996 Actor and dancer Gene Kelly and celebrated jazz singer Ella Fitzgerald pass away. http://www.kennedy-center.org/honors/history/honoree/kelly.html http://www.kennedy-center.org/honors/history/honoree/ella.html
1997 The NASA probe Pathfinder lands on Mars to conduct and transmit research.
1998 The Internet reports between 30 and 60 million users.
1999 NATO bombing begins in Kosovo when Albanians are forced from their homes by repressive Serbs.
2000 George W. Bush is President-elect, garnering enough electoral votes but losing the popular vote.
2001 The centennial of musician Louis Armstrong's birth is celebrated!