A painting bought by Queen Victoria as a Christmas present for Prince Albert, which was long thought to be a fake, has proven to be a genuine work.

Art historians have discovered that the Portrait Of A Lady And Her Son, which dates from around 1510 to 1540, is by the German master Lucas Cranach the Elder.

The newly attributed work, which is part of the Royal Collection, is now on show at Windsor Castle.

Victoria gave the painting to her beloved husband Albert as a Christmas gift in 1840 – the year they married.

The double portrait shows an unidentified consort of a Prince-elector of the Holy Roman Empire and her son, their hands clasped together.

It was later believed to be by Franz Wolfgang Rohrich, an early 19th Century artist, who was a prolific imitator of Cranach and produced over 40 versions of this portrait, and sold them as original works by Cranach.

The Royal Collection Trust’s conservators and curators used infrared reflectography to look beneath the paint surface, revealing preliminary underdrawing typical of Cranach’s work.

Analysis of the pigments, metal leaf and the application of paint provided further evidence that the portrait was a 16th Century work. X-rays of the painting and DNA analysis also proved the genuine nature of the piece.

Portrait Of A Lady And Her Son, c.1510-40 is shown alongside other works by Cranach in the King’s Dressing Room at Windsor Castle.