It is, writes historian Tim Thornton, "probably the greatest murder mystery in British history." Just who killed the young brothers who came to be known as the "princes in the tower"? A new study by Thornton cements the idea that the leading suspect is indeed guilty—and none other than Richard III, reports Live Science. The theory, first laid out by philosopher Thomas More in the 16th century, is that Richard ascended to the throne in 1483 after ordering the murder of his two nephews, 12-year-old Edward V and 9-year-old Richard, per Smithsonian. By More's account, Richard sent two henchman to suffocate the boys with pillows as they slept in the Tower of London. Richard became a villain of history as a result—Shakespeare added to the reputation in Richard III—but modern historians had begun to speculate that More's account was more propaganda than actual history.
Thornton, however, has discovered that More was in contact with two sons of one of the alleged murderers—this was 30 years after the fact, and their father was dead by then—and likely with the second alleged murderer himself, John Dighton. More spent months in Calais while writing his history, which is where Dighton lived, per History. Thornton lays all this out in The Journal of the Historical Association. More "wasn’t writing about imaginary people,” says Thornton in a University of Huddersfield news release. "We now have substantial grounds for believing that the detail of More's account of a murder is credible." The young princes were never seen after 1483, and remains found in the Tower of London in the 17th century may be theirs, though that has not been verified. (As for Richard III, his remains were found under a parking lot in 2012, though he then received a more dignified sendoff.)