Written by Matthew Robinson London

A red velvet bag found at a medieval mansion just outside London could hold new hints in the mystery over what became of Walter Raleigh's head following his execution for treason in 1618.

Raleigh -- a British explorer, soldier, spy, politician, courtier and all-round prominent Elizabethan -- was beheaded after falling out of favor with the royal court.

While his body is buried at St. Margaret's Church, next to Westminster Abbey, rumor has swirled about the whereabouts of his head for almost 400 years.

Some historians believe it was taken away by his widow Elizabeth, a lady-in-waiting to Queen Elizabeth I, who then embalmed it and kept it in a velvet bag.

English writer, soldier, politician, explorer and spy Sir Walter Raleigh, circa 1595. From an original engraving. Credit: Kean Collection/Archive Photos/Getty Images

An artifact matching that description has been found in the attic of West Horsley Place, Surrey, and is now under further investigation.

This property dates from 1425 and Raleigh's widow lived there until her death with the couple's son Carew. The Mary Roxburghe Trust, which oversees the running of the manor, has asked experts to examine the artifact to clarify its potential role in the mystery.

Peter Pearce, the charity's director, said : "In 1665, Carew Raleigh sold the estate ... It is known that some of the contents were included in the sale ... but, to date, we have been unable to find any further reference to the red bag.

"We are greatly encouraged by the results of the initial inspection, and now look forward to finding out more," said Pearce.

Mark Wallis, co-director of the Past Pleasures historical costume company, told The Observer newspaper: "It's clearly a bag of the period."

"Whether it held the mummified head, I couldn't say. But that Lady Raleigh lived there means that it's much more likely than it would be otherwise."

However, he warned that the bag was likely not the one used to carry Walter's head directly after his execution.

"If it did hold the head it would have been when it was mummified, and not covered in blood and gore," he said.

A red velvet bag was discovered in the attic of West Horsley Place, the former home of Sir Walter Raleigh's wife and son. Credit: Mary Roxburghe Trust

Other experts are more skeptical about the artifact, pointing to numerous reports indicating that Lady Raleigh carried away her husband's head in a red leather bag rather than a silk one.

"Almost every source on Raleigh's execution has wonderful detail of the full horror of it, and that Lady Raleigh took his head away in a red leather bag," historian Anna Beer told The Observer.

Other artifacts discovered in untouched rooms of the manor include an ancient executioner's ax.