Guildford James Hillier Mainwaring-Ellerker-Onslow was an English Liberal Party politician who sat in the House of Commons from 1858 to 1874.
- Occupation
- politician
- Position held
- member of the 20th Parliament of the United Kingdom, member of the 19th Parliament of the United Kingdom, member of the 18th Parliament of the United Kingdom, member of the 17th Parliament of the United Kingdom
- Citizenship
- United Kingdom of Great Britain and Ireland
- Born
- March 29, 1814
- Died
- August 20, 1882