[1] When the district was first established, it covered part of the western suburbs of Cook County.
[2] New boundaries were adopted in August 2001, with redistricting taking place following the 2000 United States Census.
[4] The district as redistricted in 2012 following the 2010 United States Census, included parts of Arlington Heights, Barrington, Barrington Hills, Bartlett, East Dundee, Elgin, Elk Grove Village, Hanover Park, Hoffman Estates, Inverness, Mount Prospect, Rolling Meadows, Roselle, Schaumburg, South Barrington, and Streamwood.
The district covered the entirety of Barrington, Hanover and Schaumburg townships.
[11][12] In the 2016 United States presidential election, the Democratic ticket of Hillary Clinton and Tim Kaine won a strong victory in the district over the Republican ticket of Donald Trump and Mike Pence.