The district includes all of Middlesex County except the City of London and Thames Centre Township, all of the Municipality of Chatham-Kent north of the Thames River, and excluding the former City of Chatham, and the Municipalities of Lambton Shores, Brooke-Alvinston Township, Dawn Euphemia Township, Warwick Township and the Indian reserves of Kettle Point and Walpole Island in the County of Lambton.

The retirement of longtime MP Rose-Marie Ur in 2006 allowed Bev Shipley, her Conservative opponent in 2004, to seize the riding.

The Tories have held the riding without serious difficulty ever since, including in 2015 during the Liberal surge that swept through Ontario.

According to the 2021 Canadian census[3] Ethnic groups: 91.8% White, 4.9% Indigenous Languages: 90.5% English, 1.5% Dutch, 1.2% Portuguese, 1.0% French, 1.0% German Religions: 63.6% Christian (25.1% Catholic, 10.8% United Church, 5.3% Anglican, 3.2% Presbyterian, 2.6% Baptist, 1.4% Reformed, 1.2% Pentecostal, 14.0% Other), 35.0% None Median income: $42,400 (2020) Average income: $52,400 (2020) This riding has elected the following members of Parliament:

Riding history from the Library of Parliament: