Though the parchment is a genuine 15th-century relic, Glaswegian researcher John Paul Floyd says it was displayed at an 1892 event, celebrating Columbus's discoveries, without any contemporaneous reference made to the map now drawn upon it.
After it was brought to public attention in the 1960s—complete with an outline of the Canadian coastline—experts dated the map to the mid-15th century, placing it a good 50 years before the Santa Mariá's 1492 journey. But it was always controversial, thanks to its sudden appearance in the historical record.
Floyd also found that the parchment was included in a 1926 event, again without any mention of the remarkable map of the Americas that it now contains. He believes that it was stolen at some point between then and the late 1950s, the map forged, and ultimately bound to the other medieval documents where it would be discovered. He believes that the Vinland map also includes characteristics found in an 18th-century reproduction of a 1463 world map: more evidence that it's a fake.
The British Library's head of cartographical and topographical materials says that the scientific community is taking Floyd's report seriously: "Sometimes it takes an outsider to see the obvious," he told The Sunday Times.