He had double royal lineage: his grandfather, William Hay, 1st Earl of Erroll was a great-great grandson of King Robert II of Scotland; and his maternal grandfather was James I of Scotland.

[1] He served as the Lord High Constable of Scotland, a hereditary title that was, after the king, the supreme officer of the Scottish army.

He was killed on 9 September 1513 in the Battle of Flodden,[2] near Branxton, Northumberland.

He died alongside his younger brother Thomas, King James IV of Scotland and more than a dozen dukes and earls in a decisive English victory.

[3] He married Christian Lyon, daughter of John Lyon, 3rd Lord Glamis, and had two children: He married secondly Margaret Kinloch of Cruvie, widow of Sir James Sandilands, 5th feudal baron of Calder.