In Lattimer, Pennsylvania, a coal mining region predominantly populated by Eastern European immigrants, a tragic event unfolded involving a labor strike. The miners were demanding better wages and safer working conditions amidst poor treatment by mine owners. As the miners peacefully marched to a nearby colliery in support of their demands, they were confronted by a posse led by the local sheriff, who had been summoned to manage the situation. The sheriff's posse, fearing unrest and seeking to break the strike, opened fire on the unarmed miners without provocation.

The ensuing violence resulted in the deaths of 19 miners and left numerous others injured. The brutality of the attack shocked the local community and garnered national attention, highlighting the violent struggles faced by laborers during a time of rapid industrialization in the United States. The Lattimer massacre became emblematic of the conflict between labor unions advocating for workers' rights and law enforcement acting under the influence of powerful industrial interests.

In the aftermath, the event spurred outrage and protests from labor rights advocates and led to greater activism among labor unions, who rallied around the cause for miners' rights and safety. The local and national labor movements drew lessons from the massacre, with many calling for reforms to improve labor relations and working conditions for miners nationwide, setting the stage for future labor rights advancements.