Deerfield is a north shore suburb of Chicago in Lake County, Illinois, United States, approximately 25 miles north of Chicago with a small portion extending into Cook County, Illinois. The population was 18,225 at the 2010 census, a decline of 175 from 2000. Deerfield is home to the headquarters of Walgreens, Baxter Healthcare, Business Technology Partners, Caterpillar Inc., APAC Customer Services, Fortune Brands Home & Security, Takeda Pharmaceutical Company's US HQ, Consumers Digest, and Mondelēz International. Deerfield is often listed among some of the wealthiest and highest earning places in Illinois and the Midwest. The per capita income of the village is $68,101 and the median household income is $143,729.
Originally populated by the Bodéwadmiakiwen (Potawatomi), Myaamia (Miami), Kiikaapoi (Kickapoo), Peoria, and Očhéthi Šakówiŋ (Oglala Sioux) Native Americans, the area was settled by Horace Lamb and Jacob B. Cadwell in 1835 and named Cadwell's Corner. A shopping center located on the site of Cadwell's farm at Waukegan Road and Lake Cook Road still bears that name. The area grew because of the navigable rivers in the area, notably the Des Plaines River and the Chicago River. By 1840, the town's name was changed to "Leclair". Within a decade, settler John Millen proposed a further name change to "Deerfield" in honor of his hometown, Deerfield, Massachusetts and the large number of deer living in the area. At the time, the alternate name for the village on the ballot was "Erin".