From a National Portrait Gallery press release:
IMAGINED LIVES: MYSTERY PORTRAITS 1520-1640
17 March 2010-October 2011
The National Trust’s Montacute House, near Yeovil, Somerset
A new National Portrait Gallery display of unseen paintings of 16th and 17th-century mystery figures opens at one of its regional partners, the National Trust’s Montacute House, on 17 March 2010. Over the last 450 years, the identities of the sitters featured in the portraits on display have been either lost or mistaken. This will be the first opportunity to see these portraits, which have either been recently restored or not exhibited for over half a century.
Inspired by the mystery that surrounds the unknown sitters, the Gallery has invited writers John Banville, Tracy Chevalier, Julian Fellowes, Sir Terry Pratchett, Sarah Singleton, Joanna Trollope and Minette Walters to contribute short imaginative stories on what their lives might have been like. These fantasy character sketches and fictional biographies accompany the portraits in the display and help bring the sitters to life.
New research undertaken by History of Art MA students at the University of Bristol, working with Dr Tatiana String – and supervised by the Gallery’s 16th Century Curator Dr Tarnya Cooper – has meant that they can now be brought back into full view with a clearer understanding of their past.
The display features portraits of men and women whose identities are no longer known. They appear to depict courtiers, musicians, writers, soldiers and others who hoped to preserve their memory by sitting for a portrait. They were purchased by the National Portrait Gallery from 1858 to 1971. When the identity of these portraits was disproved or disputed, the paintings were often removed from display or lent to other collections. Recent conservation work and new research has meant that some portraits can now be re-identified.
Update: I meant to add a link about the work done to identify one of these previously un-or-mis-identified portraits. The portrait subject of the story written by Tracy Chevalier is now thought to be Sir Robert Dudley, the illegitimate son of Robert Dudley, Earl of Leicester. Here is a news release from the University of Bristol about the students who made the identification.