In 1713, his lordship succeeded, by the death of his father, to the family titles and estates, and was soon after invited, together with a younger and only brother and two sisters, by the duchess of Argyle, their grand-aunt, to take up their residence with her in the Highlands, where she then lived in retirement. Here he remained until he had attained a proper age for college, when he was sent to the university of Glasgow. His biographer, Rolt, informs us, that while residing with the duchess of Argyle, the young earl had fallen desperately in love with a little Highland girl; but he unfortunately gives no account of the progress or termination of this boyish attachment. The circumstance, however, affords an early indication of the warm, chivalrous, and romantic disposition for which his lordship was afterwards so much distinguished.

While at the university he rendered himself famous amongst his fellow students by his boldness and courage. He led them on in all their battles with the citizens, headed every expedition of difficulty or danger, and stood forward on all occasions as the champion of the college, when any of its members were injured or insulted, or conceived themselves to be so. He, in short, took the whole burden of the university’s honour on his own shoulders, and guarded and protected it with the most watchful zeal and uncompromising intrepidity.

From the college of Glasgow he went to that of Edinburgh, where he remained for some time, and then returned to the retirement of the duchess of Argyle in the Highlands. Here he now prosecuted his studies under the tuition of a private preceptor, and continued this course until he attained his nineteenth year.

On arriving at this age, it was thought proper that he should, agreeably to the usual practice in the cases of young men of rank and fortune, proceed to the continent, at once to complete his education, and to improve himself by travel. With this view, he set out in the year 1721, first for London, where he remained for a short time, and thereafter to Paris. Here he entered the academy of Vaudeuil, and continued to attend that seminary during the two succeeding years. His progress in learning, and in the acquisition of every elegant accomplishment while he resided in the French capital, was so remarkable, as to excite a strong feeling of respect for his talents amongst his fellow academicians, who saw him surpassing many students of much longer standing, and attaining an eminence which left him few competitors. In horsemanship, fencing, and dancing, he was considered, even in the refined city of Paris, to be without a rival.

In 1723, he quitted the academy of Vaudeuil, but continued to reside in France till 1726. In the same year in which his lordship left the seminary just named, an incident occurred strongly illustrative of his daring and determined character. Amongst the other sights exhibited during the festivities which were held in celebration of the accession of the young French king, was that of drawing one of the fish ponds in the gardens of Versailles. The earl of Crawford was amongst the crowd assembled to witness this novelty. In pressing forward to the edge of the water to obtain a sight of the young monarch, he was rudely jostled by a French marquis. Irritated by this incivility, the earl instantly caught up the Frenchman, who was in full court dress, in his arms, and tossed him, robes, and feathers, and all, into the middle of the fish pond. The spectators, highly delighted with the unexpected exhibition, burst into immoderate fits of laughter, in which they were cordially joined by the young king himself, who eagerly inquired who the person was that had thrown the marquis into the water. The latter himself did not think fit to take any notice of the affair either at the time or at any after period.

In 1726, his lordship returned to Britain, acknowledged by all to be one of the most accomplished gentlemen of the age. On the 25th of December of the same year, he obtained a captain’s commission in one of the additional troops of the 2nd regiment of royal Scots Greys. This appointment he held till 1730, when, these troops being disbanded, he again repaired to the duchess of Argyle’s residence in the Highlands, and remained there for the next eighteen months. In January, 1732, he once more left this retirement to mingle with the world, being appointed to the command of a troop of the 7th, or Queen’s own regiment of dragoons. He was also, in the same month, elected one of the sixteen representatives of the Scottish peerage, in place of the earl of Loudon deceased. This honour was again conferred upon him at the general elections in the years 1734, 1741, and 1747.

In the month of June, 1733, his lordship was appointed gentleman of the bed-chamber to the prince of Wales. On the 18th of February, in the year following, he obtained the captain-lieutenancy of the 1st regiment of foot guards, and on the 1st of October in the same year, a company of the 3d foot guards. Notwithstanding these various appointments, the earl, who entertained from his youngest years a strong passion for military fame, finding his life but an inactive one, and the English service unlikely at the time to present him with any opportunity of distinguishing himself, sought and obtained the king’s permission to go out as a volunteer to the imperial army, the emperor being at that time engaged in a war with France.

His lordship joined the Imperialists in 1735, at Bruchsal on the Rhine, where he was received with every mark of distinction and favour by the celebrated prince Eugene of Savoy, then in command of the troops in that quarter. Finding, however, that there was no immediate appearance of active service here, his lordship, accompanied by viscount Primrose and captain Dalrymple, both volunteers like himself, proceeded to the army under count Sackendorff. The first duty imposed on them by this general was to reconnoitre the enemy, who were posted near Claussen. As they advanced towards the French lines they were met by a party of the enemy, three times the number of their own escort, and a skirmish ensued, in which count Nassau, who accompanied them, was killed, and lord Primrose severely wounded by a musket ball close beside the earl of Crawford.

On the evening of the same day, 17th October, 1735, the battle of Claussen was fought, affording his lordship an opportunity of distinguishing himself, which he did not let pass. He attached himself to the prince of Waldeck, who commanded the left wing of the Imperialists, and attended him throughout the whole of the battle. The position in which the earl was placed was the first attacked by the enemy, and was the most sanguinary part of the field. The intelligence, bravery, and good conduct of his lordship in this engagement excited the warmest admiration of the prince, and laid the foundation of his future fame as a soldier.

Preliminaries of peace between the emperor and France having been soon afterwards signed, the earl left the Imperial army, made a tour of the Netherlands and Holland, and again returned to Britain. On his arrival he was graciously received by George II., who honoured him with many warm expressions of esteem. His lordship remained at home for two years. At the end of this period, he again became desirous of exchanging the monotony of a peaceful and idle, for an active life, and sought the king’s permission to serve as a volunteer in the Russian army, under field marshal Munich, then engaged with the Imperialists, in a war against the Turks. Having obtained the royal permission to take this step, he embarked at Gravesend in April, 1738, for Petersburg. On his arrival there he immediately waited upon the Czarina, who received him with the most expressive indications of kindness and favour, and instantly appointed him to the command of a regiment of horse, with the rank of general in the Russian service.

Invested with these appointments, his lordship left Petersburg in the middle of May to join the army, which he effected after a dangerous and tedious journey of a month’s duration. Several sanguinary engagements with the Turks soon followed, and in all the earl eminently distinguished himself, both by his military skill, and fearless intrepidity. In one of these murderous conflicts, which took place on the 26th of July, and in which the Turks and Tartars were repulsed with great loss, his lordship, who was at the head of a party of Cossacks, excited the astonishment and admiration of even these bold and skilful riders, by his dexterity in horsemanship. Nor were they less delighted with the gallantry also which he exhibited in this battle, in the instance of a single combat with a Tartar, whom, after a desperate encounter, he sabred and stript of his arms. The latter he afterwards brought to England with him as objects of curiosity.

The season being now far advanced, marshal Munich thought it advisable to retire from the scene of operations, and accordingly retreated to Kiow, whither he was accompanied by the earl, who remained with him for three weeks after the cessation of hostilities. He then left Munich, and joined the Imperialists near Belgrade. The earl had now acquired a large stock of military knowledge, and had been especially improved in the art by his experience under Munich, whom he justly reckoned the first captain of the age. Six weeks after he joined the Imperial army, it was marched into winter quarters. On this occasion he attached himself to prince Eugene’s regiment, and proceeded with that corps to Comorra, thirty-three miles S.E. of Presburg. Here, and at Vienna, to which he occasionally resorted, he remained till the middle of April, 1739. During this leisure his lordship employed himself in reducing to method and system the military knowledge which he had acquired, by drawing plans, and writing observations on the Russian campaign; thus availing himself of every means and opportunity that offered, of improving himself in that art, to attain an eminence in which had been from his earliest years the great object of his ambition, and of his fondest hopes.

His lordship now joined the Imperialists assembled near Peterwaradin, under the command of marshal Wallis, and attached himself to his old friend and fellow soldier, the prince of Waldeck, lieutenant-general of infantry. In a short time after, the battle of Krotzka, near Belgrade, was fought in this engagement, the earl, while fighting the Turks at the head of Palfi’s cuirassiers, had his favourite black horse killed under him: another was immediately brought him, but he had scarcely gained the saddle when he himself was struck with a musket ball, which entering the outside of his left thigh, shattered the bone to pieces, and brought him to the ground.

Here he lay for some time in a state of utter insensibility, when he was accidentally discovered by general count Sucheri, who, on perceiving him, ordered some grenadiers to raise him up, and place him on one of his horses. This, however, was all the attention which the urgency of the moment would permit. Having been mounted on the horse he was left to his fate, and received no further assistance until the following morning, when he was found by one of his own grooms; his face deadly pale, his head uncovered, and himself holding fast by the horse’s mane with both hands to prevent his falling off.

He was now immediately carried to Belgrade, where surgical assistance was obtained. On examination of the wound it was at first deemed mortal; but although it certainly shortened his days, it was not immediately fatal. After making some progress towards recovery, his lordship left Belgrade on the 26th of September, being carried on board a vessel on the Danube, with which he proceeded to Comorra, where he arrived on the 27th of December. This place he left on the 28th of April, 1740, and sailed up the Danube to Vienna, which he reached on the 7th May. During all this time his lordship was confined to a recumbent posture by the state of his wounded limb, which still subjected him to the most excruciating agony, and continued constantly emitting splinters from the fractured bone. So desperate and severe was this wound, that his lordship walked for the first time, and even then with the assistance of crutches, only in the beginning of September, 1740; about a year and a half after he had received it.

In Vienna he remained till the 20th of September, when, being advised to try the effects of the baths of Baden, he proceeded to that quarter, and remained there till the 11th of August, 1741. His lordship, still suffering from his wound, which no expedient had yet been able to heal, now proceeded by Presburg, Vienna, and Leipsic, to Hamelen, where be arrived on the 3rd October, and had an interview with George II., who happened to be there at the time. His majesty received the earl with much kindness, and entered into a long conversation with him. On the 23rd of October he took leave of his majesty, and embarked for England. Notwithstanding his absence, the earl’s interest had not been neglected at home. In July, 1739, he was made a colonel of horse and adjutant-general, and on the 25th October of the same year, was appointed colonel of the 42nd regiment of foot, or Royal Scots Highlanders. The same inclination to forward his military views marked his return. On the 25th of December, 1741, the year in which he came to England, he was appointed colonel of the second troop of horse grenadier guards.

His lordship’s wound still annoying him, he was now advised to try the bath of Bareges in France, and having obtained, for this purpose, a pass from the French king, the Lynx British man-of-war was ordered to carry him out. With this vessel he sailed from Portsmouth on the 23rd of May, 1742, and arrived at Bourdeaux on the 30th of the same month.

Soon after landing he proceeded to Bareges, which he reached on the 12th June, and commenced a regular system of bathing, but without much effect; being still able to walk only with the assistance of a crutch and high-heeled shoe. From Bareges he went on the 16th October to Aix in Provence, where he again used the bath, and with much more benefit than he had derived from the same remedy in the former place. Leaving Aix his lordship arrived at Chambery on the 2nd of November, where he waited on the king of Sardinia, with whom he remained till the 18th, when he proceeded to Geneva. In this city he remained till the 1st of January, 1743. He then visited Milan, Genoa, Modena, Verona, and Venice, and from thence proceeded by Trieste, Gala, Lintz, and through Bohemia and Saxony, and finally joined the British army, of which field-marshal Stair was commander, at Hochstet, on the 24th of May, where George II. happened to be at the time. At the battle of Dettingen, which took place on the 16th of the following month, the earl commanded a brigade of life-guards, and conducted himself throughout that conflict with a coolness and intrepidity which greatly enhanced his reputation for courage and military skill. During the action, his lordship, on one occasion, ordered the officers of his brigade to the front, the enemy being within fifty paces of them. He then addressed his men, "Hark, my dear lads," he said, "trust to your swords, handle them well, and never mind your pistols." Placing himself then at their head, he led them on to the charge, encouraging them and animating them by his example as they advanced, the trumpets the while sounding the martial strain of "Britons, Strike Home." The soldiers obeying the instructions of their gallant leader, and participating in his enthusiasm, closed on the French, and drove them before them with prodigious slaughter. In the beginning of the battle a musket ball struck his lordship’s right holster case, penetrated the leather, and, hitting the barrel of the pistol which it contained, fell harmlessly into the case. Here it was found by his lordship, who showed it the day after the engagement to the king at Hanau, where he then was, and who, on seeing the earl approaching, exclaimed, "Here comes my champion;" following up afterwards this flattering expression of his opinion of his lordship’s merits, by the most gratifying remarks on the gallantry of his conduct on the preceding day.

In this year, (1743,) the earl was appointed colonel of the 4th or Scottish troop of horse guards, and, after the battle of Dettingen, was made a general of brigade. In May, 1744, his lordship joined the combined armies, in camp, near Brussels; but, owing to the over caution of marshall Wade no opportunity offered of again distinguishing himself during the whole of the campaign which followed. In the next year, however, this was not wanting. The duke of Cumberland, having been appointed captain general of the British forces, arrived at Brussels on the 11th of April, 1745, his lordship being then with the army as brigadier-general. The arrival of his grace was soon after (30th April) followed by the battle of Fontenoy. In this engagement his lordship conducted himself with his usual gallantry, and exhibited even more than his usual skill, particularly in conducting the retreat, which he did in a manner so masterly, as procured for him a reputation for military genius not inferior to any of that age. His lordship also wrote an exceedingly able and interesting account of the battle. On the 30th of May following, he was promoted to the rank of major-general.

The rebellion in Scotland now occurring, his lordship was ordered, in Feb., 1746, from Antwerp, where he then was, to his native country, to take the command of the Hessians employed by the government on that occasion, and whose numbers amounted to six thousand. With these troops he secured Stirling, Perth, and the passes into the lowlands, while Cumberland proceeded by the north-east coast in quest of the rebels. On this visit to Scotland, his lordship formed an acquaintance with, and afterwards married, lady Jane Murray, eldest daughter, and presumptive heiress of James, second duke of Athole. On the extinction of the rebellion, he returned to the army in the Netherlands, where he arrived early in June. At the battle of Rocoux, which took place on the 1st of October following, he commanded the second line of cavalry, with which he drove back the French infantry, and threw them into irretrievable confusion. His lordship soon afterwards accompanied the army into winter quarters at Bois le Duc. His troop of horse guards being this year disbanded, he was appointed to the command of the 25th regiment of foot on the 25th Dec. 1746.

In February following, (1747,) his lordship embarked at Flushing for England, landed at Southampton, and proceeded to Belford, where he arrived on the 3d March. Here his lordship met, by appointment, lady Jane Murray, to whom he was married on the day of his arrival. His wound, which had never yet been thoroughly healed, now again broke out from fatigue, and subjected him anew to all the pain and suffering which he had experienced immediately after receiving it. From Bedford, the earl and countess proceeded to London, from thence to Helvoetsluys, and finally to Bois le Duc, where they arrived in June. On the 22d May, his lordship, previous to his leaving England, was appointed to the command of the 2d regiment of dragoons, or royal Scots Greys, in room of the earl of Stair, deceased; and, on the 26th of September following, he was promoted to the rank of lieutenant-general.

On the conclusion of the campaign, the earl, accompanied by his countess, went to Aix-la-Chapelle, for the benefit of the baths there; being still seriously annoyed by his wound, which had again broken out after a second temporary cure. While his lordship was confined here to bed, his young countess---she had not yet attained her twentieth year—was seized with a violent and malignant fever which carried her off in four days. His lordship, who was deeply affected by his loss, and for a time wholly inconsolable, ordered that the body of his deceased lady should be embalmed, and sent over to his family burial place at Ceres in Fife. He himself remained at Aix till the opening of the campaign in 1748, when he joined the duke of Cumberland and confederate army of 150,000 men. His lordship remained with the army till the conclusion of the peace, which took place in the same year. On the 16th of February of the following year, (1749,) he superintended the embarkation of the British troops at Williamstadt, and soon after returned to London, where he died on the 25th December, in the forty-eighth year of his age, after suffering again severely from his wound. His remains were carried to Ceres, and deposited beside those of his countess.