This is the deathbed portrait of an unknown man with the hairstyle of the 1640s, commonly described as being the portrait of James, Duke of Monmouth, executed in 1685.

The Telegraph informs us that art historians are proposing to employ facial recognition software developed for Counter-Terrorism to identify the unknown subjects in some well-known works of art.

Software developed to recognise terrorist faces is being adapted to solve the mystery of portraits of unidentified people. …

A feasibility study is being conducted by two art historians and an electronic engineer at the University of California. They describe FACES (Faces, Art and Computerised Evaluation Systems) as a “new tool for art historians”. The project has received a $25,000 government grant.

Conrad Rudolph, professor of art history at the university, said: “Before the advent of photography, portraits were, almost by definition, depictions of people who were important in their own worlds. But, as a walk through almost any major museum will show, a large number of these unidentified portraits from before the 19th century have lost the identities of their subjects.”