The Azores, in the middle of the Atlantic Ocean, is a beautiful archipelago of nine islands. But who visited the Azores first?
Until recently, the first human incomers were assumed to be members of an expedition led by Portuguese sailor, Diego de Silves in 1427. He landed on Santa Maria Island and was soon followed by other Portuguese visitors, who settled permanently across the island archipelago. There is no archaeological evidence for earlier settlement, but an international team of researchers has approached the question from an entirely different perspective – that of lake sediment cores.
In a core bored into Peixinho Lake, they detected an increase in 5-beta-stigmasterol within a layer dated to between AD 700 and 850. This compound typically occurs in the faeces of livestock like cows and sheep, which never flourished on the islands until human settlement. They also observed increases in charcoal, which hinted at large fires burning near the lake. At the same time, native tree pollen dropped sharply. The investigators theorize that people had burned down the nearby forests to provide more graze for their flocks and herds. Caldereirão Lake, on another island, displayed the same profile dating to a century later. A lake on a third island yielded traces of non-native ryegrass.
While all this points to clear evidence for human settlement during the late 1st millennium AD, who were the settlers? The research team believes that they can only have been the Vikings, who were voyaging widely along European shores and into the Atlantic at the time.
Image: Fogo Lake on S. Miguel Island, Portuguese Azores
Credit: Luis Ascenso