The regiment has ever since remained as a single battalion.
As early as the autumn of 1787 (when the 74th, 75th, 76th, and 77th Regiments were ordered to be raised for service in India), Francis Humberstone Mackenzie of Seaforth, lineal descendant and representative of the old earls of Seaforth, had made an offer to the King for the raising of a Highland corps on his estates in Ross-shire and the Isles, to be commanded by himself. As the Government, however, merely accepted his services in the matter of procuring recruits for the regiments of Sir Archibald Campbell and Colonel Abercromby (the 74th and 75th), he did not come prominently forward. On the 19th of May 1790, he again renewed his offer, but was informed that Government did not contemplate raising fresh corps, the establishment of the army having been finally fixed at 77 regiments.
Undismayed, however, by the manner in which his offers had been hitherto shelved, he was the first to step forward, on the declaration of war, and place his great influence in the Highlands at the disposal of the Crown. Accordingly, a Letter of Service, dated 7th March, 1793, was granted to him, empowering him, as Lieut.-Colonel Commandant, to raise a Highland battalion, which, as the first to be embodied during the war, was to be numbered the 78th. The strength of the battalion was to be 1 company of grenadiers, 1 of light infantry, and 8 battalion companies. Seaforth immediately appointed as his major his brother-in-law, Alexander Mackenzie of Belmaduthy, son of Mackenzie of Kilcoy, a captain in the 73rd Regiment, and a man in every way fitted for the post. A notice was then posted through the counties of Ross and Cromarty, and the island of Lewis.
Applications for commissions now poured in upon Seaforth; and, besides his own personal friends, many who were but slightly known to him solicited favours for their relatives. The following is a list of those whose names were approved by the King:—
FIRST LIST OF OFFICERS.
Lieut.-Colonel Commandant.—F. H. Mackenzie, afterwards Lord Seaforth, Lieut.-Gen. 1808. Died 1815. [His portrait is on the Plate of the [Colonels of the 78th and 79th Regiments].]
Lieut.-Colonel.—Alexander Mackenzie of Belmaduthy, afterwards of Castle Fraser, when he assumed the name of Fraser. Lieut.-General 1808. Died 1809.
Majors.
George, Earl of Errol, died 1799.
Alexander Mackenzie of Fairburn, Lieut.-General 1809.