The 1920 census revealed that the U. S. population had surpassed 100 million.

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Television was displayed for the first time in 1927, but full scale development was delayed nearly two decades.

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In the fight for control of the bootleg liquor trade in Prohibition Chicago, 7 gang members were killed in the St. Valentines Day Massacre in 1929.

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The Museum of Modern Art was opened in 1929 with an exhibition of paintings by Van Gogh.

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Franklin D. Roosevelt was seized by polio in 1921, a disease that left him crippled for life.

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The first road for motor vehicles was opened in 1921.

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The first Miss American pageant was held in 1921.

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The first paid advertisement on the radio was broadcast in 1922.

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In 1926, the Book of the Month club was formed

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Penicillin was discovered in 1928

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FM radio was introduced in 1929

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The Supreme Court ruled against minimum wage laws in 1923

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The culmination of 44 years of work, the Oxford English Dictionary appears in 1928

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Henry Ford's Model T automobile accounted for over half of all cars sold in America in 1920.

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In 1923, Hitler was arrested and sentenced to 5 years in prison.

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Robert Frost, one of the most familiar poets in American literature, won the Pulitzer Prize in 1924.

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The "Little Orphan Annie" comic strip appeared in 1924.

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Writing under the name "Agatha Christie" Mary Clarissa Miller launched an enormously successful career as a mystery writer in 1921.

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Channel No. 5 made a splash in 1921, becoming the world's best selling perfume.

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The first successful treatment for diabetes occurred in 1922, when insulin was isolated and used to save the life of a young man.

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In 1920, "Babe" Ruth was sold to the New York Yankees from the Boston Red Sox for $125,000.

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The first radio broadcast of a baseball game was made by Graham McNamee from the Polo Grounds in New York in 1921.

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The number of illegitimate births in Germany was 173,000 in 1921.

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The 1921 Nobel Prize for Physics went to Albert Einstein for his discovery of the photoelectric effect.

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The Philadelphia A's went through a dry spell of 20 games with not a single win in 1923.

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The first birth control clinic in the United States opened in New York in 1923.

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Ford Motor Company produced its ten millionth car in 1924.

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By 1924, there were 2.5 million radios in use in the United States.

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The Charleston became the fashionable dance in 1925

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Sex education in schools was forbidden in Tennessee in 1925.

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The Harlem Globetrotter basketball team was organized by Abe Saperstein in 1927.

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Amelia Earhart was the first woman to fly across the Atlantic in 1928.