Proby was the son of William Proby of Elton Hall, Huntingdonshire and formerly of Fort St George, Madras, who was son of Charles Proby, and a remote heir of Sir Peter Proby through his cousin John Proby. John Proby died in 1710, then his daughter Frances in 1711, and William Proby inherited. He was also heir to his paternal grandfather, Emmanuel Proby who was the fourth son of Sir Peter Proby.
Charles Proby was a close ally of Sir Edward Winter in the power struggles in Madras of the 1660s. He predeceased Dorothy his wife, who died in 1685; he is said to have been living in 1684. He had another son, Charles, who became rector of Tewin, and there was a daughter, Elizabeth, who married Gabriel Roberts at Fort St. George in 1687.
William Proby went to Fort St George, Madras as an employee of the East India Company, and was a writer there in 1683. He was secretary of the Council there in 1688, under Elihu Yale as President. In 1702 he moved to Surat, where he was second on the Council. He served in that capacity for about a decade, under Nicholas Waite, Ephraim Bendall and William Aislabie. According to Inscriptions on Tombs or Monuments in Madras, William Proby was discharged by the Company.
There is conflicting information about William Proby and his family. His mother, Dorothy (née Torriano), went on to marry Thomas Lucas, and died in 1685 in Madras. According to one source, William married Frances Gray (née English, widow of Thomas Gray) in 1693, and had two children with her, John and Editha. The children returned with him to England. Editha married Sir John Osborne, 7th Baronet, with whom she had six sons and four daughters, and died in 1745.
William Proby is also recorded as married to Henrietta, daughter of Robert Cornewall, and Henrietta is given as mother of John Proby. The family seat was Elton Hall, then in Huntingdonshire. The Proby inheritance also included the manor of Ranes (Raans, Raynes, Amersham) in Buckinghamshire; it was sold in 1735. William Proby was High Sheriff of Buckinghamshire in 1719. John Proby succeeded his father William in 1739.
Proby was admitted to Jesus College, Cambridge in 1715. He was elected to the House of Commons for Huntingdonshire in 1722, a seat he held until 1727, and later represented Stamford from 1734 to 1747.
Proby died in March 1762.
- John Proby (1720–1772), succeeded his father as Member of Parliament for Stamford and was elevated to the peerage as Baron Carysfort
- William Proby
- Thomas Proby (1723 – 8 July 1758), killed at Fort Ticonderoga in the Battle of Carillon
- Capt. Charles Proby (1725–1799) RN
- Baptist Proby (d. 1807), became Dean of Lichfield
Jane Proby died in 1726.
- Mosley, Charles, ed. (2003). Burke's Peerage, Baronetage & Knighthood (107 ed.). Burke's Peerage & Gentry. p. 3223. ISBN 0-9711966-2-1.
- Cotton, Julian James (1905). "Inscriptions On Tombs Or Monuments In Madras 1st 1905 Ed". Internet Archive. Madras: Superintendent, Government Press. pp. 3, 4, 7. Retrieved 14 October 2017.
- Burke, John; Burke, Bernard (1841). A Genealogical and Heraldic History of the Extinct and Dormant Baronetcies of England, Ireland, and Scotland. Genealogical Publishing Com. ISBN 9780806307398. Retrieved 14 October 2017.
- "Parishes: Elton, British History Online". Retrieved 15 October 2017.
- Pine, Leslie Gilbert. New Extinct Peerage. Heraldry Today. p. 60. ISBN 0-900455-23-3.
- Bhattacharya, Sudip (29 July 2013). The Strange Case of Lord Pigot. Cambridge Scholars Publishing. p. 37. ISBN 9781443851206. Retrieved 15 October 2017.
- Urquhart, William (1809). "The Oriental Obituary". Internet Archive. Madras. p. 40. Retrieved 15 October 2017.
- Charles F. McIntosh, The Proby Family of England and of Hampton and Norfolk, Virginia, The Virginia Magazine of History and Biography Vol. 22, No. 2 (Apr., 1914), pp. 217–220, at p. 218. Published by: Virginia Historical Society. JSTOR 4243352
- "Proby, Charles (PRBY684C)". A Cambridge Alumni Database. University of Cambridge.
- "Roberts, Gabriel (b.c.1665), of Ampthill, Beds., History of Parliament Online". Retrieved 15 October 2017.
- Love, Henry Davidson. Indian Records Series Vestiges of Old Madras 1640-1800. Mittal Publications. p. 483. Retrieved 14 October 2017.
- Love, Henry Davidson. Indian Records Series Vestiges of Old Madras 1640–1800. Mittal Publications. p. 508. Retrieved 14 October 2017.
- Records of Fort St. George: Diary and Consultation Book. Superintendent, Government Press. 1894. p. 145.
- Collins, Arthur; Brydges, Sir Egerton (1812). Peerage of England. F.C. and J. Rivington [and others]. p. 141. Retrieved 14 October 2017.
- "Proby, John (c.1698-1762), of Elton Hall, Hunts". Retrieved 19 June 2016.
- Salmon, Nathaniel (1759). A Short View of the Families of the present Irish Nobility, etc. William Owen. p. 246. Retrieved 14 October 2017.
- Lipscomb, George (1847). The History and Antiquities of the County of Buckingham. J. & W. Robins. p. xviii. Retrieved 14 October 2017.
- "Proby, John (PRBY715J)". A Cambridge Alumni Database. University of Cambridge.
- Northamptonshire, England, Church of England Baptisms, Marriages and Burials, 1532–1812