The Cook County Poor Farm (also known as the Dunning Poorhouse and Insane Asylum) was a public institution established by the Cook County Board of Commissioners of Illinois in 1851 to provide care for the destitute, infirm, and mentally ill of Cook County. The 320-acre property, located ten miles northwest of Chicago, was situated in what was once Jefferson Township, which became known as Dunning in 1883. It included the Poorhouse, the Insane Asylum, support buildings, a working farm and a cemetery. Later, two additional hospitals were built, along with a small schoolhouse for the inmates' children. The working farm produced most of the food required for inmates and staff. Flax was also grown to make linens, sheets and some clothing for the inmates. The County Commissioners administered all funds, appointed the staff, and supervised the operation of the Poor Farm.
With the growing number of inmates and its designation as Cook County’s only Potter's Field, the cemetery reached capacity by the 1860s, prompting the addition of new burial grounds. The Poor Farm's inmate population grew quickly, leading to overcrowding. The county built a new, larger Insane Asylum in 1870. The Poorhouse had fallen into disrepair by the 1870s and it could not accommodate the increasing number of inmates. In 1882, the county built a railroad line to the Poor Farm to facilitate the transportation of people and supplies during the construction of a new Poorhouse. Construction on a new Poor house began in the early 1880s and was finished in 1885. The county renamed the facility the "Infirmary." Consumptives had been part of the Poor Farm inmate population since the beginning, and were housed in a small building. Increased demand to care for consumptives at Dunning led to the building of a new Tuberculosis hospital, completed in 1903. After 1900, due to the escalating costs and challenges of caring for the large population at Dunning, the State of Illinois took over responsibility for the Infirmary, the Insane Asylum and the Tuberculosis Hospital. The Poor Farm at Dunning was sold to the state in 1912. The Insane Asylum patients remained on site and the inmates of the Infirmary and the Tuberculosis hospital were transferred to a newly constructed Infirmary in Oak Forest, Illinois.
Complaints about the conditions at the Poor Farm and the treatment of the inmates were an ongoing challenge for the County Commissioners. Charges by inmates and observers concerning abuse, neglect and substandard living conditions were typically investigated by several County Commissioners or a committee appointed by the County. Crimes were investigated by both the County and the police. The local newspapers often did their own investigations and wrote exposes on the conditions at the Insane Asylum and the Poorhouse. From the firing of an incompetent, non-licensed physician in the 1850s to the beating death of inmates by attendants in the 1890s, the Poor Farm was often in the headlines of the Chicago newspapers.