Population growth in the land, especially in urban population was in part due to industrialization of the nation. The increasing factory businesses created many more job opportunities in cities and people began to flock from rural, farm areas to large urban locations. Minorities and immigrants added to these numbers. In 1870, there only two American cities with a population of more than 500,000, but by 1900, there were six. Three of these namely Philadelphia, Chicago and New York had over 1 million inhabitants.