Mackenzie was the son of Simon Mackenzie, of Lochslin (died about 1666), who was himself a son of Kenneth Mackenzie, 1st Lord Mackenzie of Kintail and a brother of George Mackenzie, 2nd Earl of Seaforth. The Mackenzies were a clan from Ross-shire that had risen to prominence in the 15th century during the disintegration of the Lordship of the Isles. George's mother was Elizabeth, the daughter of the Reverend Peter Bruce, of St Andrews.
Mackenzie was born in Dundee. The exact year of his birth is uncertain. The biography published in the folio edition of his works (1716-1722) suggests that he was born in 1636, but he himself in his own work, The Religious Stoic, declared in 1663 that he was not yet 25.
He was educated at the King's College, University of Aberdeen (which he entered in 1650), the University of St Andrews and the University of Bourges, France.
He was elected to the Faculty of Advocates in 1659, and distinguished himself in the trial of Archibald Campbell, 1st Marquess of Argyll in 1661. He was a member of the Scottish Parliament for Ross from 1669 and in 1677 became Lord Advocate and a member of the Privy Council of Scotland. As Lord Advocate he was the minister responsible for the persecuting policy of Charles II in Scotland against the Covenanters. He resigned for a short time in 1686, taking up office again in 1688. He opposed the dethronement of James II, and to escape the consequences he retired from public life. He founded the library of the Faculty of Advocates, which opened in 1689.
When the leading Scottish jurist Sir John Lauder, Lord Fountainhall was, in 1692, offered the post of Lord Advocate he declined it because the condition was attached that he should not prosecute the persons implicated in the Glencoe Massacre. Sir George Mackenzie, who had previously been a Lord Advocate, also refused to concur in this partial application of the penal laws, and his refusal (unlike Fountainhall's) led to his temporary disgrace.
The inhumanity and relentlessness of his persecution of the Covenanters gained him the nickname of "Bloody Mackenzie", and despite being responsible for the deaths of approximately 18,000 covenantors, his legacy continues to influence historians through his popularity and significance in Scottish history. In private life he was a cultivated and learned gentleman with literary tendencies, and is remembered as the author of various graceful essays, of which the best known is A Moral Essay preferring Solitude to Public Employment (1665). He also wrote legal, political, and antiquarian works of value, including Institutions of the Law of Scotland (1684), Antiquity of the Royal Line of Scotland (1686), Heraldry, and Memoirs of the Affairs of Scotland from the Restoration of Charles II, a valuable work which was not published until 1821. Mackenzie was the founder of the Advocates' Library in Edinburgh. He retired at the Revolution to Oxford. He died at Westminster on 8 May, 1691 and is buried in Greyfriars Kirkyard in Edinburgh, his mausoleum being designed by James Smith.
In 1662 Mackenzie married Elizabeth, daughter of George Dickson of Hartree, one of the Senators of the College of Justice. They had:
John (died young)
Simon (died young)
George (died young)
Agnes, who married James Stuart, later 1st Earl of Bute
Elizabeth, who married first Sir Archibald Cockburn of Langton and secondly the Hon Sir James Mackenzie of Royston, Bt.
His first wife died not later than 1667-1668 and in 1670 he married secondly Margaret Haliburton, daughter of Haliburton of Pitcur. They had two sons and two daughters, of whom only one son, George, survived him. The younger George married and had one daughter, who died without issue.
Since late 1998, Greyfriars Churchyard has been the site of unexplained events linked in the popular imagination to the ghost of Mackenzie, two days after a "vagrant" had broken into his tomb to find shelter . More than 500 attacks had been reported in 2006. Visitors reported being cut, bruised, bitten, scratched and most commonly blacking out. Some complained later of bruises, scratches and gouge-marks on their bodies. Most attacks and feelings of unease occurred in MacKenzie's Black Mausoleum and the Covenantors Prison. An exorcist, Colin Grant, tagged along by journalist Claire Gardener,was brought in to perform an exorcism ceremony, but soon claimed that the forces were too overpowering, and feared that they could kill him. A few weeks later, he died of a heart attack. [1].
Edinburgh City Council closed off that part of the cemetery until an Edinburgh-based historian and author, Jan Andrew Henderson, persuaded the council to allow controlled visits to that part of the churchyard and in turn this developed into a nocturnal guided tour, which became a local attraction. Of the visitors who have taken the tour, over 400 have reported feeling various sensations of being touched, pulled, grabbed or similar and many of them have returned home to find dark bruising and/or deep scratches on their faces, necks, hands, bodies or legs. Greyfriars Churchyard and, in particular, MacKenzie's Poltergeist, have been featured on paranormal TV programmes, including Fox's Scariest Places on Earth, and ITV's Extreme Ghost Stories.
On Monday 15 September 2008, the team from the US show Ghost Adventures were seen filming outside the Covenantors Prison.
