Workers organized labor unions in the late 1800s to advocate for better working conditions, wages, and benefits. They used tactics like strikes and boycotts to push for change against low pay, long hours, and dangerous work. Several important unions formed, including the Knights of Labor which welcomed all workers, and the American Federation of Labor which focused on skilled trades. However, business owners opposed unions, using lockouts and hiring replacements to break strikes, while the government often sided with owners over workers through interventions like sending troops. This led to violent clashes between labor and management.