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Cook County, Illinois

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  • Cornelius Zeilenga (1916 - 1987)
    Residence : Washington, Sioux, Iowa - 1920* Residence : Washington, Sioux, Iowa, USA - 1920* Residence : Washington - Jan 1 1925* Residence : Sioux, Iowa, USA - Jan 1 1925* Residence : Homewood, Cook, ...
  • Anje Evenhuis (1854 - 1951)
    Residence : 1526 South Austin Blvd, Cicero, Cook, Illinois Residence : Cook, Illinois, 1526 South Austin Blvd, Cicero Residence : 1930 - Chicago (Districts 0751-1000), Cook, Illinois, United S...
  • William John Ellis (1857 - 1939)
  • Annetta Backes (1906 - 1931)
  • Ruth Lydia Belden (1904 - d.)

This project is for those who were born, lived, and died in Cook County, Illinois.

Cook County is a county in the U.S. state of Illinois. It is the second-most populous county in the United States after Los Angeles County, California. As of 2015, the population was 5,238,216. Its county seat is Chicago, the largest city in Illinois and third-most populous city in the United States. More than 40% of all residents of Illinois live in Cook County.

Cook County's population is larger than that of 29 individual U.S. states, and the combined populations of the seven smallest states. There are 135 incorporated municipalities partially or wholly within Cook County, the largest of which is Chicago, which is home to approximately 54% of the population of the county.

That part of the county which lies outside of the Chicago city limits is divided into 29 townships; these often divide or share governmental services with local municipalities. Geographically, the county is the sixth-largest in Illinois by land area. It shares the state's Lake Michigan shoreline with Lake County. Including its lake area, the county has a total area of 1,635 square miles (4,234.6 km2), the largest county in Illinois, of which 945 square miles (2,447.5 km2) is land and 690 square miles (1,787.1 km2) (42.16%) is water. Land-use in Cook County is mainly urban and densely populated.

Cook County is included in the Chicago-Naperville-Elgin, IL-IN-WI Metropolitan Statistical Area. It is surrounded by what are known as the five collar counties.

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