Franklin was pleased with Wright's portrait, and requested that the artist paint a copy of it for his friend William Hodgson (1745-1851), of London. On the back of that painting is written: "This portrait of Doctor Franklin was painted in Paris in 1782 and was presented by him to Mr William Hodgson, of Coleman Street, as a token of his regard and friendship." That this was a portrait by Wright is supported by an October 14, 1782 letter from Hodgson to the shipper of the painting. Hodgson includes payment and asks that the shipping costs be refunded "to Mr Wright, for the picture, which, when proper opportunity offers, I am expecting." Formerly in the Corcoran Gallery of Art, this portrait is now in the National Gallery of Art.

That Franklin did indeed pose for Wright, even if just for final touches, is confirmed by two letters to William Temple Franklin, Franklin's grandson and secretary in Paris. In Joseph Wright to William Temple Franklin, n.d. (Fall 1782), Wright writes that he has finished the Franklin portrait and 2 copies (one for his mother, and the other for Mr. Whitford [sic]). Caleb Whitefoord was Richard Oswald's secretary in Paris, William Temple Franklin's counterpart. In Caleb Whitefoord to William Temple Franklin, June 30, 1784, Whitefoord writes that he has lent a copy of Wright's Franklin portrait to the artist Benjamin West, who was then at work on an oil sketch of the Jay Treaty commissioners (unfinished, Winterthur Museum, Delaware). Whitefoord also writes that he intends to have Wright paint two more copies of the Franklin portrait, for him to present to "Mrs. Hewson" and "Mr. Strahan." Six years later, in 1790, Whitefoord presented his own copy of Wright's Franklin portrait to the Royal Society of London for Improving Natural Knowledge.

Attributions of authorship became even more confused after Joseph-Siffred Duplessis painted his own life-size head-and-bust Portrait of Benjamin Franklin in 1785, based on the same 1778 pastel portrait. This image was later popularized by a widely-reproduced 1868 engraving by Henry Bryan Hall. Wright did not sign and date his Franklin portraits, and they were mistakenly presumed to have been copies after Duplessis's 1785 oil-on-canvas portrait, instead of copies after Duplessis's 1778 pastel portrait. These presumptions were proven wrong by Charles Henry Hart in the early 20th century.

The Franklin portrait at the Pennsylvania Academy of the Fine Art (above) was purchased by Joseph Harrison, Jr. in England in 1850 or 1851. The seller was the estate of London merchant William Vaughn, and was "always considered by him an original portrait," i.e. painted from life.

According to Christie's Auctions, Wright painted seven versions of the Franklin portrait:

• Life portrait (1782), Franklin's diplomatic gift to Richard Oswald; "Auchincruive," Ayrshire, Scotland (1782-1922); 1922 purchase by William Smith Mason; Mason's 1936 gift to Yale University Art Gallery
  • Copy (1782), for Patience Wright, the artist's mother
  • Copy (1782), commissioned by Caleb Whitefoord, secretary to Richard Oswald. Whitefoord's 1790 gift to the Royal Society of London.[1]
  • Copy (1782), commissioned by Franklin for his friend, William Hodgson. Ex-collection: Corcoran Gallery of Art. National Gallery of Art, Washington, D.C.[2]
  • Copy (after 1782), commissioned by Richard Oswald for his brother or nephew, Boston Public Library
  • Copy (1784?), commissioned by Whitefoord for Mrs. Hewson, on loan to Benjamin West, June 1784
  • Copy (1784?), commissioned by Whitefoord for Mr. Strahan, presented to Strahan by June 1784

Sources:

• Charles Henry Hart, "An Original Portrait of Doctor Franklin, by Joseph Wright" The Pennsylvania Magazine of History and Biography, vol. 32, no. 3 (1908), pp. 320-334.
• Catalogue of Pictures, Statuary and Bronzes in the Gallery of Joseph Harrison, Jr., Rittenhouse Square, Philadelphia. (privately printed, 1870), p. 6.
• Coleman C. Sellers, Benjamin Franklin in Portraiture (New Haven, CT: Yale University Press, 1962), pp. 414-426.
• A Catalogue of the Collection of American Paintings in the Corcoran Gallery of Art, Volume 1 (Washington, D. C.: The Corcoran Gallery of Art, 1966), p. 31.
• Monroe H. Fabian, Joseph Wright, American Artists, 1756-1793 (Washington, D.C.: National Portrait Gallery, 1985), p. 87.
• Important American Paintings, Drawings & Sculpture of the 18th, 19th & 20th Centuries (New York: Christie's Auctions, 26 May 1992), Lot 16.