Historian AJ Morton said the eight-letter "Shugborough Code" inscription, OUOSVAVV, which has long been the subject of speculation at Shugborough Hall in Great Haywood, England, was likely put in place by relatives of the Shephard's Monument creator, Thomas Anson, The Daily Telegraph reported Tuesday.
Morton said popular theories about the letters included a code left by the Knights Templar pointing toward the Holy Grail, but the more likely explanation involves Anson's nephew, George Adams, and his wife, Mary Vernon-Venables, who lived at the estate in the 19th century.
"There doesn't appear to be any reference to the curious letters until the 19th century. This suggests, quite strongly, that they were added later," Morton said. He said the letters likely referred to the couple, their relatives and locations.
"I've tried convincing myself that I'm wrong, but I can't see any way out. While I'm pleased to have solved it, I do worry that I've destroyed something magical," he said.