List of Heirs of Scotland - The Great Cause

The Great Cause

Scotland was ruled by the six Guardians of Scotland on behalf of the child-heir Margaret. However, other powerful nobles claimed the throne, and in an attempt to avoid a civil war the Regents appealed to King Edward I of England for assistance. By the Treaty of Birgham, 1290, Margaret was placed under Edward's guardianship and betrothed to his eldest son, the Prince of Wales. Margaret set out from Norway for Scotland in the autumn of that year, but was taken ill on the voyage and died at Orkney on 26 September 1290, age seven. Scotland was left without an heir and with two claimants, so the Guardians of Scotland again appealed to Edward I to act as an arbitrator between the Competitors for the Crown of Scotland. The two strongest claimants were

• Dervorguilla of Galloway, died 1290 and was succeeded by her son: John de Balliol, grandson of Margaret of Huntingdon, the elder daughter of David, Earl of Huntingdon, the younger brother of King William the Lion (see above), and
• Robert de Bruce, Lord of Annandale, son of Isobel of Huntingdon, Margaret of Huntingdon's younger sister.

Though Bruce invoked proximity of blood and claimed to have been made Tanist of the Kingdom by the then-childless Alexander III, Balliol was the genealogically senior heir, and Edward declared in his favour following an election at Berwick-upon-Tweed, 3 August 1291.