Alexander Stewart, Earl of Buchan, Alasdair Mór mac an Rígh, and called the Wolf of Badenoch (1343 – 20 June 1405), was the third surviving son of King Robert II of Scotland and youngest by his first wife, Elizabeth Mure of Rowallan. He was the first Earl of Buchan since John Comyn, from 1382 until his death. Alexander married the widowed Euphemia I, Countess of Ross, but they had no children although he did have a large family by his longtime mistress, Mairead inghean Eachann. Alexander was Justiciar of Scotia for a time, but not an effective one. He held large territories in the north of Scotland before eventually losing a large part of them. Alexander is remembered for his destruction of the royal burgh of Elgin and its cathedral. His nickname was earned due to his notorious cruelty and rapacity but there is no proof that it was used during his lifetime.
Known in charters as Alexander Senescalli (Latin for Steward), is first noted when, on 14 August 1370, he issued letters patent from Ruthven Castle undertaking to grant protection to the Bishop of Moray and all of his lands, men and property in Badenoch. His father, Robert the Steward, had acquired the lands of Badenoch probably from Euphemia, Countess of Moray who had become his second wife. Robert had a petulant relationship with his uncle, King David II of Scotland. In 1368 he and his sons were required by David's parliament to take an oath that they would keep their undisciplined followers in check—later that year, Robert and Alexander were imprisoned in Lochleven Castle. possibly as a result of these oaths having been broken