Labor Day is a dedication to the social and economic achievements of American workers. It constitutes a yearly national acknowledgment to the contributions that workers have made to the strength, prosperity and well-being of our country. It has evolved from a purely labor union celebration into a general "last fling of summer" festival. The origin and deeper meaning of the day has been forgotten, or never actually known to many. The beginnings of the American Labor Movement started with the Industrial Revolution. Once factory systems began to grow, a demand for workers increased. They hired large amounts of young women and children who were expected to do the same work as men for less wages. New immigrants were also employed and called "free workers" because they were unskilled. Child labor in the factories was not only common, but necessary for a family's income. Children as young as five or six manned machines or did jobs such as sweeping floors to earn money. No laws prevented the factories from using these children, so they continued to do so. "Sweatshops" were created in crowded, unsanitary tenements. These were makeshift construction houses, dirty and unbearably hot. The United States had the highest job-related fatality rate of any other industrialized nation in the world. Men and women earned twenty to forty percent less than the minimum deemed necessary for a decent life. People lived and worked in unhealthy environments in poverty with little food. The country was growing and its economy was rising, but its people were miserable. The first large national labor organization to become popular was the Noble and Holy Order of the Knights of Labor. It was founded in 1869 by garment workers in Philadelphia who believed that one union of skilled and unskilled workers should exist. The union was originally a secret, but later was open to all workers, including blacks, women and farmers. Five hundred thousand workers joined in a year.