The portrait of a young boy dressed in blue is on display as part of an exhibition opening on Tuesday - 100 years to the day after it was last shown publicly in London.
"'The Blue Boy' is not only one of the most famous pictures by Gainsborough, I think it's one of the most famous pictures in British art altogether," Gabriele Finaldi, the National Gallery's director, told Reuters.
The painting had hung at the gallery for three weeks in the winter of 1922 before crossing the Atlantic Ocean after it was bought by U.S. railroad magnate and art collector Henry E. Huntington from the Duke of Westminster.
"It is a remarkably beautiful picture, it's striking, it's moving, it's beautifully painted, it's enormously sort of romantic," Finaldi said of Gainsborough's 1770 work.
In order to show Gainsborough's passion for Anthony Van Dyck, "The Blue Boy" is on display along with a couple of the Flemish artist's works as well as two other paintings by Gainsborough.
"Van Dyck was very important for the consciousness of the history of Britain (and) also British painting...And so he (Gainsborough) dresses this anonymous young man, we're not quite sure who he is - in Van Dyck costume," Finaldi said.
The London exhibition marks the first time "The Blue Boy" has been loaned from the California-based Huntington Library, Art Museum, and Botanical Gardens.
(Reporting by Sarah Mills, editing by Ed Osmond)
By Sarah Mills
