Concern for social problems among Chicago's immigrant poor led Jane Addams and Ellen Gates Starr to found Hull House in 1889.During the 1870s and 1880s, Chicago attained national stature as the leader in the movement to improve public health.The Ottawa, Ojibwe, and Potawatomi tribes had ceded additional land to the United States in the 1816 Treaty of St. The Potawatomi were forcibly removed from their land after the Treaty of Chicago in 1833.
Chicago's first railway, Galena and Chicago Union Railroad, and the Illinois and Michigan Canal opened in 1848.
), officially the City of Chicago, is the third-most populous city in the United States.
With over 2.7 million residents, it is also the most populous city in both the state of Illinois and the Midwestern United States. The Chicago metropolitan area, often referred to as Chicagoland, has nearly 10 million people and is the third-largest in the United States.
Chicago's flourishing economy attracted huge numbers of new immigrants from Europe and migrants from the Eastern United States.
Of the total population in 1900, more than 77% were either foreign-born or born in the United States of foreign parentage.