On May 1, 1886, unions in the United States launched a general strike to demand an eight-hour workday. It was a time when the right to organize and strike did not exist. A few days later, police violently broke up a peaceful mass meeting at Haymarket Square in Chicago where 80,000 workers had gathered. A number of people were killed and many injured. Shortly thereafter 7 labour leaders were arrested and four of them were executed by hanging. One chose to take his own life while in custody.