History of Will County, Illinois in Timeline

Will County, Illinois, is located in the northeastern part of the state and is the fourth-most populous county in Illinois, with a population of 696,355 in 2020. Its county seat is Joliet. Will County is part of the Chicago–Naperville–Elgin, IL–IN–WI Metropolitan Statistical Area, making it one of the Chicago collar counties. The county utilizes multiple area codes, including 815 and 779 for the Joliet area, 630 and 331 for the northern part, and 708 for the central and eastern regions.

1969: Fourth Courthouse Completed

In 1969, the fourth Will County courthouse, designed in the Brutalist style, was completed.

1972: Joliet Refinery Construction

In 1972, the Joliet Refinery, owned and operated by ExxonMobil, was constructed along the Des Plaines River.

1980: Presidential Election

In 1980, Will County voted for the national winner in the presidential election, a trend that continued until 2012.

January 1985: Record Low Temperature

In January 1985, a record low temperature of -26 °F (-32 °C) was recorded in Joliet.

June 1988: Record High Temperature

In June 1988, Joliet recorded a record high temperature of 104 °F (40 °C).

1988: Republican Streak Ends

In 1988, Will County voted Republican, continuing a trend from 1892 with only three exceptions.

2010: 2010 Census Data

As of the 2010 Census, Will County had 677,560 people, 225,256 households, and 174,062 families residing in the county.

2012: Voted for National Winner

In 2012, Will County voted for the national winner in the presidential election, continuing a trend that began in 1980.

2016: Hillary Clinton Wins

In 2016, Hillary Clinton, who was born in Chicago, won Will County in the presidential election.

2020: Jennifer Bertino-Tarrant Takes Office

In 2020, Jennifer Bertino-Tarrant took office as the county executive of Will County.

2020: 2020 Census

In 2020, the census recorded Will County's population at 696,355, making it Illinois's fourth-most populous county.

2020: New Courthouse Completed

In 2020, the new Will County courthouse, designed by Wight & Co., was completed.

2022: Courthouse Listed as Endangered

In 2022, the Landmarks Preservation Council of Illinois included the 1969 Will County courthouse on its “Most Endangered Historic Places in Illinois" list.