South Northamptonshire is a constituency^{[n 1]} represented in the House of Commons of the UK Parliament since its 2010 recreation by Andrea Leadsom, a Conservative who served as Secretary of State for Business, Energy and Industrial Strategy until 13 February 2020. She was Leader of the House of Commons from 2017 to 2019, and Secretary of State for Environment, Food and Rural Affairs from 2016 to 2017. ^{[n 2]} The seat of South Northamptonshire is considered a Conservative safe seat, having elected a Conservative MP at every election for 110 Years. Current Conservative MP Andrea Leadsom was re-elected in 2019 with an increased majority.

This is a rural seat around Towcester and Brackley but also includes the southern edge of Northampton. There is a significant motorsport sector including Silverstone.^[2] Incomes and house prices are above average for the UK.^[3]

Before 2010, the constituency existed from 1832 to 1918, and from 1950 to 1974, however on different boundaries during each period. It elected two Members of Parliament (MPs) by the bloc vote system of election from 1832, until the representation was reduced in 1885 to one member elected by the first past the post system.

Prominent members

Three names feature prominently among the area's Commons members, the 3rd and 5th Earl Spencer (during their tenures as MP having a courtesy title only, Viscount Althorp – Althorp is a major country house in the seat, well known as the childhood home of Diana, Princess of Wales); Edward Fitzroy (son of Lord Southampton), Speaker of the House of Commons from 1928 until his death in 1943; and lastly, Reginald Manningham-Buller, 1st Viscount Dilhorne who on accomplishment of a peerage sat for the final two years of his life as the historic equivalent of the President of the Supreme Court of the United Kingdom with additional functions, the Lord Chancellor.

In the 19th century history of the seat the Cartwright family (with three members) lived in the stately home Aynhoe Park near Banbury.

History of boundaries

The seat was abolished in 1918 to form the new constituency of Daventry, then recreated in 1950 caused by a relatively short-lived abolition of Daventry. In 1974 the constituency was almost wholly swallowed up by a reborn Daventry, which on wide boundaries saw substantial population growth.

This called for recreation in 2010 whereby most of the electoral wards were taken from the former version of the Daventry seat.

Present bordering constituencies

The constituency is bordered by Daventry and Northampton South to the north, Wellingborough to the north east, Milton Keynes North and Milton Keynes South to the south east, Buckingham to the south, Banbury to the south west and Kenilworth and Southam to the west.

1832–1885: The Hundreds of Kings Sutton, Chipping Warden, Greens Norton, Cleley, Towcester, Fawsley, Wymersley, Spelhoe, Nobottle Grove, and Guilsborough.^[4]

1885–1918: The Sessional Divisions of Brackley and Towcester, and part of the Sessional Division of Daventry. (The part of the Sessional Division of Daventry included in South Northamptonshire excluded the parishes of Ashby St. Ledgers, Barby, Claycoton Crick, Elkington, Kilsby, Lilboume, Long Buckley, Stanford, Watford, West Haddon, Winwick, and Yelvertoft, which were assigned to Mid Northamptonshire). ^[5]

1950–1974: The Boroughs of Daventry and Brackley, and the Rural Districts of Brackley, Daventry, Northampton, and Towcester.

2010–2021: The District of South Northamptonshire wards of Astwell, Blakesley, Blisworth, Brackley East, Brackley South, Brackley West, Chase, Cogenhoe, Collingtree, Cosgrove, Courteenhall, Deanshanger, Grafton, Kings Sutton, Kingthorn, Little Brook, Middleton Cheney, Salcey, Silverstone, Steane, Tove, Towcester Brook, Towcester Mill, Wardoun, Washington, Whittlewood, and Yardley, and the Borough of Northampton wards of East Hunsbury, Nene Valley, and West Hunsbury.

2021-present: The District of West Northamptonshire wards of Brackley, Bugbrooke (part), Deanshanger, Duston West and St. Crispin (part), East Hunsbury and Shelfleys, Hackleton and Grange Park, Middleton Cheney, Nene Valley, Silverstone, Sixfields (part) and Towcester and Roade.

• List of parliamentary constituencies in Northamptonshire