Here's what Wikipedia has to say:

Alexander "Sawney" Bean(e) was the legendary head of a 48-member clan in 15th- or 16th-century Scotland, reportedly executed for the mass murder and cannibalisation of over 30 to 40 people.

The story appears in The Newgate Calendar, a crime catalogue of the notorious Newgate Prison in London. While historians tend to believe that Sawney Bean never existed, his story has passed into legend and is part of the Edinburgh tourism industry.

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