After the Russian Revolution of 1917, many southern and eastern European immigrants were blamed for causing strikes and spreading revolutionary ideas.
In 1919, US President Woodrow Wilson appointed Alexander Mitchell Palmer as his Attorney General.
Palmer claimed that Communist agents were trying to overthrow the American government and he ordered the arrest of over 10,000 suspected communists and anarchists.
Almost 250 were deported back to their home countries.
Ferdinando Nicola Sacco and Bartolomeo Vanzetti were suspected communists.
They were convicted of murdering two men during a 1920 armed robbery of a shoe factory in South Braintree, Massachusetts.
After a controversial trial and a series of appeals, the two Italian immigrants were executed on 23 August 1927.
The case divided opinion in America with many believing that the men were on trial for their radical beliefs, not the crimes that they were accused of.
This idea was echoed by Vanzetti himself in his final statement in court.