Thanks to William Shakespeare, the name Macbeth has become byword for political ambition realised by bloody violence. The character of Macbeth in the celebrated Shakespearean tragedy is based on an actual Scottish king who lived and died five hundred years before he was immortalised.

However, the Macbeth thus conjured up bears almost no resemblance whatsoever to the king who ruled Scotland between 1040 and 1057. In fact, it is difficult to exaggerate how great an injustice history and Shakespeare have inflicted on Mac Bethad mac Findlaich.

Fiona Watson has uncovered, buried beneath the layers of myth, a history that is entirely different from, but just as extraordinary as, that recounted by Shakespeare. The historical Macbeth was a remarkable man living in turbulent times. As ruler of Alba (Scotland) he sat on one of the oldest and most established thrones in Western Europe.

It is true that he killed Duncan, the previous king, but this was the normal, if brutal, method of regime change in Dark Age Scotland. Duncan's rash behaviour, culminating in a humiliating military defeat in northern England, was reason enough to prompt his removal before Scotland's security was further compromised.

The reality is that Macbeth quickly established himself as an effective and popular ruler. As a Celtic warrior-king, he was responsible for the maintenance of his people's dominance of northern Britain. A friend to the Church and valiant protector of his people, the real Macbeth epitomised the contemporary model of vigorous medieval kingship. His fascinating story, long overdue in the telling, is done full justice in Fiona Watson's authoritative and compelling narrative.