The 16th-century artwork was found as First Court, the oldest part of Christ’s College, Cambridge, was restored.
Its motifs of a red Lancastrian rose, portcullis and a fleur-de-lis – not seen since the 1700s – celebrate patron Lady Margaret Beaufort, who gave birth to Henry VII, the first Tudor monarch.
After being established as God’s House in 1437, the college moved to its present site in 1448, before it was re-founded as Christ’s in 1505 byLady Margaret – and the portcullis was the emblem of her family.
Historian Dr Christina Faraday said: “Margaret left her indelible mark on the college and it is an early example of her family’s savvy use of visual ‘branding’.
“Henry VII had a very weak claim to the throne but became adept at using visual symbols like this to promote his kingship.
“Such survivals are extremely unusual as wall paintings were a relatively cheap and disposable form of decoration and so were rarely deliberately preserved.”
The 20ft-wide design was likely located in the original library and last visible in 1738, archives show.
