[citation needed] In 1790, he became a major-general, and in 1793 was appointed to command the Guards Brigade in the Duke of York and Albany's army in Flanders during the French Revolutionary Wars.

[2] As lieutenant-colonel Lake went out with drafts to America in the spring of 1781, made the campaign in North Carolina under Lord Cornwallis, and commanded the grenadiers of the guards and of the old 80th royal Edinburgh regiment in a sortie, under Colonel Robert Abercromby, from the British lines at York Town, which inflicted heavy loss on the French and American besiegers, on 11 October.

[3] Hugh Wodehouse Pearse reports that "Lake was one of the three field officers selected by lot to take charge of the troops in captivity, but, as he was anxious for private reasons to proceed to England, Major Gordon of the 76th [sic] [80th] Regiment generously volunteered to take his place.

[4] In December 1796, he was appointed commander in Ulster and issued a proclamation ordering the surrender of all arms by the civil population,[2] during which time he was 'untroubled by legal restraints or by his troops' violent actions'.

[6] Lake succeeded Sir Ralph Abercromby as Commander-in-Chief, Ireland in April 1798 and turned his attention to Leinster, where 'public floggings and torture of suspected rebels became widespread and added to the general atmosphere of terror'.

Hely-Hutchinson shouldered much of the blame, but it was accepted that Lake's troops were inexperienced and a head-on battle with the seasoned French force was probably to be avoided.

He took up his duties at Calcutta in July 1801, and applied himself to the improvement of the East India Company army, especially in the direction of making all arms, infantry, cavalry and artillery, more mobile and more manageable.

He then took Delhi (11 September) and Agra (10 October), and won a victory at the Battle of Laswari (1 November), where the power of Scindia was completely broken with the loss of 31 disciplined battalions, trained and officered by Frenchmen, and 426 pieces of ordnance.

This defeat, followed a few days later by Major-General Arthur Wellesley's victory at the Battle of Argaon, compelled Scindia to come to terms, and a treaty was signed in December 1803.

[11] Cornwallis succeeded Lord Wellesley as Governor-General of India in July of that year – superseding Lake at the same time as commander-in-chief – and determined to put an end to the war.

At the conclusion of the war he returned to England, and in 1807 he was created Viscount Lake of Delhi and Laswary and of Aston Clinton in the County of Buckingham.