King James V died only days later on 14 December 1542 and Mary succeeded as Queen of Scots under the Earl of Arran's regency. This was not disputed by the contemporary Earl of Menteith, the other potential claimant. However, when the third Earl's great-grandson William was confirmed as Earl of Strathearn and heir-of-line of Robert II's eldest unquestionably legitimate son David in 1631, he began to boast that he had a better claim to the throne than the then King, Charles I. He was swiftly removed from his offices and deprived of the Earldom of Strathearn in 1633, being given the inferior title of Earl of Airth.