1730-87. He was the fourth of seven sons and fourteen children of the M.P Sir James Johnstone Bart of Westerhall, Dumfriesshire, and of his wife Barbara Murray, the daughter of the 4th Lord Elibank. He was the older brother of Captain Gideon Johnstone, and a number of his other brothers rose to prominence in parliament, the East India Company, and in the accumulation of wealth.
Having served his early career in a number of vessels and spent time in the merchant service, Johnstone first came to notice as a midshipman when upon leaving the Lark 44 he challenged and wounded Captain John Crookshanks in the neck for refusing him a certificate. On 8 March 1748 he put his undoubted fearlessness to better use when serving with the Canterbury 60, Captain David Brodie, he boarded a fireship approaching his squadron off Port Louis, Hispaniola, and made fast a line in order that she could be towed away.
He passed his lieutenant?s examination on 2 February 1749, but being unable to secure employment returned to the merchant service. He was eventually commissioned lieutenant of the Sutherland 50, Captain Edward Falkingham, on 9 October 1755, moving to the Biddeford 20, Captain Hon. Robert Digby a few months later, on which vessel his brother Gideon was already serving. Again he earned some notoriety by killing the captain?s clerk in a duel, whilst on 22 February 1757 he was court-martialled aboard the Dreadnought 60 in Port Royal, Jamaica and found guilty of insubordination and disobedience. Being severely reprimanded, he did not return to the Biddeford but was appointed to the Augusta 60, Captain Arthur Forrest, remaining on the Jamaican station. Having then been seconded to the Dreadnought 60, Captain Maurice Suckling, he was aboard that vessel in company with the Augusta and Edinburgh 64 when they drove off three French sail of the line, a 50-gun ship and three frigates near Cap Fran?ois on 21 October 1757. Johnstone was praised by Suckling and Forrest for his bravery in this action, but typically he blotted his copybook by falling out with the commander-in-chief of the station, Rear-Admiral Thomas Cotes, over prize-money in June 1758.
From August 1758 he served aboard the Trial 14, Captain Thomas Cookson, whom he attempted unsuccessfully to bring to a court martial for incompetence, and he saw further service in the Downs aboard the Preston 50, Commodore William Boys, prior to being invalided ashore. In June 1759 he briefly served as acting captain of the Essex 70 for Captain John Campbell.
On 6 February 1760 Johnstone was appointed commander of the sloop Hornet 10, serving in the North Sea and on the Lisbon station. With this slow, sluggish vessel he enjoyed much success against the enemy privateers by removing her mizzenmast at sea and disguising her as a weaker vessel, two of his captures being the privateer Chevalier D?Artesay off Granville on 8 January 1761 and Societ? 6 a week later. On learning of the Spanish declaration of war against England he displayed great enterprise by commissioning a vessel and despatching her with this news to the West Indies, thereby allowing Rear-Admiral George Brydges Rodney to take offensive action against Spanish possessions that were still in ignorance of the commencement of hostilities.
Johnstone was subsequently posted to the Hind 20 on 11 August 1762, but whilst awaiting her arrival at Chatham from Gibraltar he suffered a severe fall that left him in bed for three months with a broken ankle. During this period another captain, William M?Cleverty, took his commission and Johnstone was placed on half-pay prior to joining the Wager 20 towards the end of the year.
Benefitting from a friendship with the secretary to the prime minister, the Earl of Bute, Johnstone was appointed governor of West Florida on 20 November 1763. This posting was greeted with a furious attack upon him in the ?North Briton?, and resulted in Johnstone physically assaulting the journalist who was only saved from severe injury by members of the public. Johnstone was charged and bound over to keep the peace. Whilst in West Florida he performed excellent service in attracting trade and immigrants to the territory, but after failing to co-operate with the military, and then planning a war against the Creek Indians in defiance of government policy, he felt obliged to return home in 1767 with his departure only briefly preceding his dismissal by the government.
In May 1768 Johnstone was elected M.P. for Cockermouth, and over the next few years he enjoyed an active role in the House of Commons, taking a particular interest in attempting to maintain the independence of the East India Company from governmental interference, and in speaking out against the slave trade and naval impressment. He also joined the opposition Rockingham group which bitterly opposed the government?s management of the American colonies, and Johnstone correctly predicted the troubles to come with rebellion and French intervention. In December 1770 he fought a duel with Lord George Germain following one of his typical outbursts in the House of Commons, and he continued to sit in parliament as the member for Appleby from 1774-80 in preference to Cockermouth where he had been re-elected.
In early 1778 he was appointed to treat with the American colonies, the government being aware of his sympathies towards the rebels but accepting that he was now strongly opposed to the granting of independence. Sailing with his fellow commissioners the Earl of Carlisle and William Eden aboard the Trident 64, Captain John Elliot, he soon managed to alienate the American Congress with a bungled attempt to win over one of their members, and with an accusation of bribery hanging over his head he was dismissed from the peace commission. He remained in the colony only long enough to condemn the American leaders whom he had previously praised for their virtue, and to urge every mode of warfare on the rebels.
Upon returning to England and crossing the floor in parliament, he vociferously defended the government?s employment of German mercenaries and made frequent assaults in his typical un-gentlemanly manner upon Admirals Hon. Augustus Keppel and Lord Howe for their failure to annihilate their opponents, although in so doing he only displayed his lack of technical knowledge. Even the first lord of the Admiralty, Lord Sandwich, found his irksome conduct detrimental to the government, so in order to get him out of the country Johnstone was appointed commodore and commander-in-chief of a squadron to be based off Portugal. The fact that Johnstone contributed so many votes to the government allowed Sandwich to overlook the far more worthy Vice-Admiral Sir Robert Harland for this command, although at least he paid no heed to Johnstone?s supporters who insisted that his talents merited the command of the Channel fleet.
There followed a few months spent in the Channel under Admiral Sir Charles Hardy, presumably to gain some basic grounding in his profession, and Johnstone served in the retreat of August 1779 aboard the Romney 50 with Captain Robert Nicholas as his flag-captain. In September, the allied fleet having left the Channel, he briefly raised the flag of Rear-Admiral Sir John Lockhart-Ross aboard the Romney in order to investigate rumours of a French invasion force congregating at Cancale Bay, but these proving groundless he returned to Spithead.
On 11 November 1779, in proceeding to take up his command off Portugal, Johnstone?s pennant ship Romney, Captain Roddam Home, stood by as the Tartar 28, Captain Alexander Graeme, and sloop Rattlesnake, Lieutenant John M?Laurin, captured the Spanish frigate Santa Margaritta 34. Johnstone resided ashore at Lisbon during the entire year of 1780 whilst his squadron performed excellent service off Cape Finisterre, the most spectacular being the capture of the excellent French frigate Artois 38 on 3 July, and the Perle 18 three days later. Typically the government gave Johnstone the credit for the captures, and in December 1780 he was elected M.P for Lostwithiel in their interest, the seat having been provided by a Treasury minister, John Robinson, who was the brother of Captain Hugh Robinson.
After briefly returning to England, and following the Dutch entry to the war, Johnstone was ordered to proceed on a secret mission at the end of 1780 with a strong force to capture the Cape, it having initially been mooted that he lead an expedition to the River Plate and perhaps attack the Spanish settlements in the Pacific Ocean. Clearly the government were keen to send him away as far as possible whilst harvesting the votes of his allies in parliament. With his broad pennant flying once more aboard the Romney 50, Captain Roddam Home, and joined by a convoy of East Indiaman and three thousand troops under Colonel William Medows, he set sail from Spithead on 13 March in the company of the Channel fleet which was bound for the relief of Gibraltar.
Whilst on passage to the Cape, Johnstone?s squadron anchored off Porto Praya in the Cape Verde island of St Jago. Unfortunately he totally neglected to form a defensive position against any possible assault by a French force under the Balli de Suffren, which having received intelligence of Johnstone?s mission was known to be taking the same route. On 16 April Suffren duly arrived, and noting the poor dispositions of Johnstone?s ships he sailed straight into the attack. Fortunately for Johnstone the French captains were not as tactically aware as their commander, and in their failed assault only two vessels became fully engaged, these being easily beaten off and then subjected to a cursory pursuit. Seeking a scapegoat to cover up his lamentable performance, Johnstone returned to the bay and placed Captain Evelyn Sutton of the Isis 50 under arrest for failing to get his ship ready for the chase of the enemy, even though she was partially dismasted at the time. He also refused an instant court-martial on his subordinate, claiming that there was not the time to arrange it, and Sutton was therefore still under confinement when the squadron sailed for the Cape on 30 April.
In the event Suffren got to the Cape first, so on 21 July Johnstone launched an attack on a rich Dutch East Indiamen convoy in Saldanha Bay instead. Although the Dutch ran their ships ashore and set them alight, the British succeeded in putting the fires out on all but one vessel, which upon drifting down towards the squadron was grappled by a party personally led by Johnstone and towed away to explode ten minutes later. Following this event the ships destined for the East Indies, including the Isis with the imprisoned Captain Sutton, continued on their passage, whilst Johnstone hoisted his broad pennant aboard the frigate Diana 36, Captain Sir William Burnaby, and returned to Lisbon to get married.
Johnstone later returned to England, and after being placed on half-pay he continued to sit in parliament in the government interest, although he still advocated less interference in the affairs of the East India Company. He tried unsuccessfully to attack Admiral Lord Howe?s conduct in the relief of Gibraltar at the end of 1782, yet he spoke out against the new government?s recall of Admiral Lord Rodney, whom he praised for the tactical brilliance of his victory at the Battle of the Saintes. In 1784 he was appointed a director of the East India Company, and after losing out on a Treasury borough and failing to get elected independently in 1784 he re-entered parliament as the M.P. for Ilchester in February 1786, becoming a supporter of William Pitt?s government.
Meanwhile Captain Sutton was justly acquitted at his court martial following his return to England, and Johnstone subsequently lost a legal claim for false imprisonment, being required to pay five thousand guineas compensation to the victim. After two appeals, one of which saw the sum increased, the House of Lords upheld the verdict, but in the meantime Johnstone had been increasingly suffering from ill health and he resigned his parliamentary seat in February 1787.
On 24 May 1787, having been two years an invalid, Johnstone died at Hotwells, Bristol, with Captain Sutton?s compensation remaining unpaid.
On 31 January 1782 Johnstone married Deborah Charlotte Dee, known as Charlotte, the daughter of the late vice-consul to Lisbon, and they had issue one son. She later married Admiral Sir Charles Edmund Nugent in 1790 after three years as a widow. Previously Johnstone had fathered four illegitimate children with his American mistress, Martha Ford, one of whom, George Lindsay Johnstone, served as an M.P from 1800-13 and shared many of his father?s traits.
Known as ?Governor Johnstone?, apparently ironically, he was certainly brave but was also insulting, tactless and utterly shameless as an M.P. Despite his initial recommendation of sensible measures in order to placate the Americans he was stupid, arrogant, foul-tempered, and could be overtly un-diplomatic, as was illustrated in his eventual demand that scalping and extermination be used on the rebellious colonists. He was clumsy and lacked grace, his language was direct and coarse if animated, but nevertheless it could be effective in parliament where Johnstone was recognised as a good orator. A proud man who followed his own course, his friends found him generous and loyal and he was even apparently able to display friendship and generosity to his enemies. Nevertheless, his conduct towards Captain Sutton illustrated that he was totally shameless in looking to his own interests.