Geoffrey Chaucer | Geoffrey Rush | Geoffrey of Monmouth | Geoffrey Moull | Geoffrey Hill | Geoffrey Keezer | Geoffrey de Montbray | Geoffrey Wilkinson | Geoffrey Howe | Geoffrey Blainey | Geoffrey Robertson | Geoffrey Keating | Fenton John Anthony Hort | The Sketch Book of Geoffrey Crayon, Gent. | Geoffrey Palmer | Geoffrey Hartman | Geoffrey C. Hazard, Jr. | Simon Fenton | Michael Fenton Stevens | Geoffrey Robinson | Geoffrey Owens | Geoffrey Layton | Geoffrey Gurrumul Yunupingu | Geoffrey de Mandeville | Geoffrey de Luterel | Geoffrey Burbidge | Geoffrey | Geoffrey Winthrop Young | Geoffrey Whitehead | Geoffrey Taylour, 4th Marquess of Headfort |
Sir William was the eldest son of James Parsons of Diseworth, Leicestershire, and Catherine, sister of Sir Geoffrey Fenton, the Secretary of State to Elizabeth I.
Massinger's sources for Italian history in the relevant era were William Thomas's The History of Italy (1561) and Francesco Guicciardini's Historia d'Italia, most probably in Geoffrey Fenton's translation (third edition, 1618).