Blackadder is a genuine surname, its usage in the UK currently documented back to the 15th century, which may explain the choice of the name, with the first series being set in this time period. The name is thought to be mostly Scottish in origin, which is not contradicted in the series, as the first Blackadder begins as the Duke of Edinburgh. However, the Scottish name means 'black water' and the first series clearly links the name to the snake. (There is footage of a black snake in the opening credits.) In the third series it is revealed that a branch of the Blackadder family is a significant clan in Scotland, although they have become known by the name MacAdder. There is a Clan Blackadder in reality. The late Dr Eric Blackadder, Chief Medical Officer at the BBC at the time of the first programme, made the unlikely claim that the series is named after him.