Macbeth (anglicised from Mac Bethad mac Findlaích; born c.1005, died 15th August 1057) was King of Scotland from 1040 until his death. He took the throne after killing his predecessor, Duncan I. It is not clear whether he murdered him treacherously, as depicted in Shakespeare's play, or whether he simply killed him in battle. It is also unclear whether he had any hereditary claim to the throne. Much later sources say his mother was a member of the royal family, but this cannot be historically proved. It has also been suggested that his wife's grandfather, whose name is known to have been Kenneth, may have been Kenneth II or Kenneth III, so he may have had a claim jure uxoris. Duncan himself might be considered a usurper, having succeeded his grandfather, Malcolm II, the first example of succession by a descendant. Previously, the throne had always alternated between branches of the royal house. Macbeth was sufficiently secure on the throne to undertake a pilgrimage to Rome. He was killed at the battle of Lumphannan against the forces of Duncan's son Malcolm. He was succeeded briefly by his stepson, Lulach, and then by Malcolm, who became Malcolm III.