Archibald Douglas, 8th Earl of Angus and 5th Earl of Morton (1555-1588), was the son of David, 7th earl. He succeeded to the title and estates in 1558, being brought up by his uncle, James Douglas, 4th Earl of Morton, a Presbyterian.
In 1573 he was made a Privy Councillor and Sheriff of Berwickshire; in 1574 Lieutenant-General in Scotland; in 1577 Warden of the West Marches and Steward of Fife; and in 1578 Lieutenant-General of the realm.
He gave a strong support to Morton during the attack upon the latter, made a vain attempt to rescue him, and was declared guilty of high treason on June 2, 1581. He then entered into correspondence with the English government for an invasion of Scotland to rescue Morton, and on the latter's execution in June went to London, where he was welcomed by Queen Elizabeth.
After the Raid of Ruthven in 1582 Angus returned to Scotland and was reconciled to King King James, but soon afterwards the king shook off the control of the Earls of Mar and Gowrie, and Angus was again banished from Court.
In 1584 he joined the rebellion of Mar and Glamis, but the movement failed, and the insurgents fled to Berwick-upon-Tweed. Later they took up residence at Newcastle-upon-Tyne, which became a centre of Presbyterianism and of projects against the Scottish government, encouraged by Elizabeth, who regarded the banished lords as friends of the English and antagonists of the French interest.
In February 1585 they came to London, and cleared themselves of the accusation of plotting against James's life. A plan was then prepared for their restoration and for the overthrow of James Hamilton, 2nd Earl of Arran. In October they invaded Scotland and gained an easy victory over Arran, captured Stirling Castle with the King in November, and secured from him the restoration of their estates, and the control of the government.
In 1586 Angus was appointed Warden of the Marches and Lieutenant-General on the Border, and performed good services in restoring order; but he was unable to overcome the king's hostility to the establishment of Presbyterian government.
In January 1586 he was granted the Earldom of Morton with the lands entailed upon him by his uncle; this made him 5th Earl of Morton.
Burke, Messrs. John and John Bernard, The Royal Families of England, Scotland, and Wales, with their Descendants, etc., volumer 2, London, 1851, pedigree CLXXVII.