THE mysterious history of one the most famous paintings in Glasgow's collections is to be investigated by a major new international art project.

For many years there have been question marks over the true creator of The Lady in a Fur Wrap, an enigmatic painting in Glasgow's collections.

It has long been attributed to El Greco, the Greek-born, Spanish-based artist considered one of the finest painters of the Spanish Renaissance.

Now examinations have begun by experts from Scotland and Europe on paintings related to the masterpiece to try and find out more about the Lady in a Fur Wrap's history and attribution.

Five paintings that could provide clues to the Lady's attribution and the identity of the model are a Portrait of a Knight in Armour, attributed to the Circle of El Greco, Don Juan of Austria, attributed to Jorge de la Rúa, Anne of Austria by Alonso Sánchez Coello, King Philip II of Spain by Alonso Sánchez Coello and Portrait of a Gentleman, firmly attributed to El Greco.

The Lady in a Fur Wrap was displayed at the Louvre in 1838–48 and was attributed to El Greco (1541–1614), whose real name was Domenikos Theotokopoulos.

It was regarded as an early masterpiece of the painter, believed to be have been painted soon after he settled in Spain in the 1570s.

William Stirling Maxwell, the Scottish politician, 10th Baronet of Pollok, and art historian, praised the portrait in his study Annals of the Artists of Spain (1848), the first scholarly history of Spanish art in English.

He later purchased the portrait and since 1967, when Pollok House and most of its collections were given to the City of Glasgow by Stirling Maxwell’s granddaughter, the Lady in a Fur Wrap has been on public display within the House.

However, there is disagreement over who painted the picture, and when, and who is featured in the painting.

In 2004, Gabriele Finaldi, director of the Prado for a time and now director of the National Gallery in England, said it was a "problematic picture", adding: "In other words it looks less and less like an El Greco."

Pippa Stephenson, curator of European Art at Glasgow Museums, said there was great debate about the attribution of the painting.

"There really are so many different views, it is impossible to say whether there is a majority in favour of one view or another, and this is why we are opening up this new area of investigation to try and find out as much as we can," she said.

The five related paintings are to be studied by a group of experts from the University of Glasgow, Glasgow Museums, the Museo Nacional del Prado in Madrid and the National Trust for Scotland, who care for Pollok House.

The project will explore "questions of artistic technique, attribution and identity, using scientific analysis as well as research methods involving the history of dress, society and collecting".

Duncan Dornan, head of Glasgow Museums, said: "We are pleased to partner with the foremost experts in the field of Spanish art to gain a fuller understanding of this iconic painting’s creation through comparative study of related works in our collection.

"We look forward to learning more about these major paintings of the Spanish Golden Age, including one of Glasgow Museums’ most popular and internationally recognised artworks."