What significant event in u. s immigration history took place in the 1920s

January 1, 1920 - For the first time, the 1920 census indicates apopulation in the United States over 100 million people. The 15% increase since the last census now showed a count of 106,021,537. The geographic center of the United States population still remained in Indiana, eight miles south-southeast of Spencer, in Owen County.

January 10, 1920 - The League of Nations is established with the ratification of the Treaty of Versailles, ending the hostilities of the first World War. Nine days later the United States Senate votes against joining the League.

February 3, 1920 - The first performance of the play, Beyond the Horizon, is held. The play by Eugene O'Neill would win the first of his four Pulitzer Prizes.

August 18, 1920 - Women are given the right to vote when the 19th Amendment to the United States constitution grants universal women's suffrage. Also known as the Susan B. Anthony amendment, in recognition of her important campaign to win the right to vote.

September 17, 1920 - The American Professional Football League is formed in 1920 with Jim Thorpe as its president and eleven teams. It would change its name to the National Football League in 1922.

November 2, 1920 - A landslide victory for Warren G. Harding in both the Electoral College and popular vote returns the Republican Party to the White House. Harding gained over 16 million popular votes to Democratic candidate James M. Cox's 9 million and won the Electoral contest with a 404 to 127 landslide. This was the first election in which women had the right to vote.

The Immigration Quota was established

which statement explains one of the reasons world war 1 was so much more destructive than earlier conflicts

i do not know? i think i have seen this before though h?