Sir Denis Mahon, the distinguished art historian, started collecting Italian Baroque paintings during the mid-1930s when such works were out of fashion and important paintings could be bought for relatively small sums. The collection includes masterpieces by Guercino, Guido Reni, Domenichino, Luca Giordano and Johann Liss. By the early 1970s, the importance of these artists was universally recognised.
The entire collection was exhibited at the National Gallery in 1997. At that time Sir Denis announced that at his death, the majority of his pictures would be bequeathed to the National Art Collections Fund. They would then be put on display in several British collections for the pleasure and benefit of the public.
The National Gallery has been lent 27 pictures which greatly strengthens the display of 17th- and 18th-century Italian painting. Some artists are now represented in the Gallery for the first time: Bartolomeo Schedoni, the refined Parmese painter, Valerio Castello from Genoa, who was strongly influenced by Van Dyck, and the highly precocious Bolognese painter, Donato Creti.
The loans supplement the Gallery's own holdings of the works of certain major artists. The National Gallery now offers the best selection of the works of Guercino, and holds pictures by Guido Reni which span the artist's whole career.