Sir Henry Williams, also known as Sir Henry Cromwell, was a knight of the shire (MP) for Huntingdonshire during the reign of Elizabeth I. He was the grandfather of the Protector, Oliver Cromwell.

Huntingdonshire was a Parliamentary constituency covering the county of Huntingdonshire in England. It was represented by two Members of Parliament in the House of Commons of England until 1707, then in the House of Commons of Great Britain from 1707 to 1800, and then in the House of Commons of the Parliament of the United Kingdom from 1801 to 1885.