The town is west of Milwaukee in Waukesha County in an area originally inhabited by Potawatomi Indians.

In May 1838, Jacques Vieux Jr., with a large party of white settlers, led the local Potawatomi west.

The town was served by the Milwaukee and Mississippi Railroad (now the Canadian Pacific Rail), which also erected a depot in 1853, forming the Brookfield Junction.

[5] This quiet, rural atmosphere attracted one notorious resident, Al Capone, as he established an area to live and a distillery on Brookfield Road.

The City of Brookfield was incorporated from 17.5 square miles of the central and eastern parts of the town on August 14, 1954.

[5] The next year, the Village of Elm Grove was also organized out of a 3.25 square mile part of the town in the east.

[10] According to the United States Census Bureau, the town has a total area of 5.5 square miles (14.3 km2), all of it land.