Every year, people across the world commemorate Labor Day on May 1, also known as May Day.
So what is the story behind this holiday?
In the late 1800s, American workers faced twelve-hour workdays, seven days a week under very difficult conditions.
Eventually, labor unions had had enough, and on May 1, 1886, hundreds of thousands of people went on strike across the country, calling for eight-hour workdays.
Three days later, a bomb went off in Chicago's Haymarket Square, the city at the center of the unrest
as tensions escalated between strikers and strike breakers, killing seven police officers and four civilians.
The event only sparked a stronger push for workers' rights.
But it wasn't until nearly a decade later that President Cleveland signed into law Labor Day as a holiday in 1894.
But in the U.S., the holiday was set for the first Monday in September.
It was an attempt to distance any association with the Haymarket Riots.
May Day eventually became a huge celebration in the former Soviet Union, marked by large military parades.
May 1 continued to be recognized as Labor Day across the rest of the world as the holiday was eventually embraced internationally.