The constituency consisted of the historic county of Northamptonshire. Although the county contained a number of parliamentary boroughs, each of which elected one or two MPs in its own right for parts of the period when Northamptonshire was a constituency, these areas were not excluded from the county constituency. Owning freehold property of the required value, within such boroughs, could confer a vote at the county election. (After 1832, only non-resident owners of forty shilling freeholds situated in borough seats could qualify for a county vote on the basis of that property.)
As there were sometimes significant gaps between Parliaments, the dates of first assembly and dissolution are given for those up to 1640. Where the name of the member has not yet been ascertained or is not recorded in a surviving document, the entry unknown is entered in the table.
^Elected following the elevation of Sir Edward Montagu to the peerage in 1621
^From: 'List of members nominated for Parliament of 1653', Diary of Thomas Burton esq, volume 4: March - April 1659 (1828), pp. 499-500. URL: http://www.british-history.ac.uk/report.aspx?compid=36965. Date accessed: 27 January 2008.
Cobbett's Parliamentary history of England, from the Norman Conquest in 1066 to the year 1803 (London: Thomas Hansard, 1808) [2]
The House of Commons 1690-1715, by Eveline Cruickshanks, Stuart Handley and D.W. Hayton (Cambridge University Press 2002)
J E Neale, The Elizabethan House of Commons (London: Jonathan Cape, 1949)
The Parliaments of England by Henry Stooks Smith (1st edition published in three volumes 1844–50), second edition edited (in one volume) by F.W.S. Craig (Political Reference Publications 1973))