Lieutenant-Colonel Sir John Scott Lillie, C.B., who was born in 1789, was commissioned Ensign without purchase into the 1/6th Foot on 31.3.1807, and embarked shortly afterwards with the Regiment, under Sir Brent Spencer, for service in the Peninsula. After cruising off Barbary, Cadiz and the Tagus, the 1/6th joined the Army under Arthur Wellesley and Lillie was duly present at Roleia on 17.8.1808 and Vimeira on 21.8.1808. In the autumn of 1808, Lillie was attached to the 1st Battalion, Loyal Lusitanian Legion, a Portuguese Corps of three Infantry Battalions raised under Sir Robert Wilson (see A Very Slippery Fellow, The Life of Sir Robert Wilson, 1777-1849, by Michael Glover) and financed by the exiled Portuguese Regency. He served briefly on Wilson's Staff, being promoted Lieutenant in the Legion during the period of recruitment in the North near Oporto. On 27.9.1810, he was present with the Legion at the Battle of Busaco, and in May 1811, when the Legion's Battalions were taken into the Portuguese Army as the 7th, 8th and 9th Cacadores, Lillie continued with the 7th Cacadores. He was subsequently present with that Corps at Redinta, Pombal, the capture of Campo Mayor, the sieges of Oliveria, and between March and April 1812, the assaults and capture of Badajoz.
On 22.7.1812, Lillie was present with the 7th Cacadores at the Battle of Salamanca, 'where he is reputed to have captured personally the Colours of the 116th French Line Regiment during the struggle for the Arapiles'. And in the following year he participated in the actions of Aldea de Ponte and Osma, where he was wounded on 19.6.1813, the Battle of Vittoria on 21.6.1813, and the blockade of Pamplona. Promoted to the command of the 7th Cacadores, he was next present at the Battle of the Pyrenees, the actions of Irun, St. Martial, the capture of St. Sebastian, the passage of the Bidossa, and the Battle of Nivelle, where he was again wounded on 10.11.1813. On the same day he was advanced to Captain without purchase in the 60th Rifles having been promoted Lieutenant in the 6th Foot in March 1810. Lillie next commanded the 7th Cacadores at Orthes on 27.2.1814 and at Toulouse on 10.4.1814, where he was very severely wounded and 'left on the battlefield for 48 hours, his comrades thinking him dead'. In respect of these wounds he was awarded a pension of £250 per annum commencing 1815 or 1816, and received accelerated promotion to Brevet Major.
In March 1816, Lillie was knighted by patent, being ineligible for a K.C.B., and, being a Captain in the British Army (substantive), not eligible for a C.B. He finally attained the rank of Major, without purchase, in June 1817 and was placed on Half-Pay with the reduction of the additional Battalion on 24.12.1818. Returning to Full-Pay in the 46th Foot, then in India, in 1827, 'but being unable from the nature of his wounds to serve in a tropical climate', he returned to Half-Pay in the 31st Regiment in 1828.
In 1831, Lillie was appointed by Don Pedro of Portugal a Major-General in the Portuguese Army and ordered to organise and command an expedition of British and French volunteers to assist him in his struggle for the Government of Portugal. And in September 1831, he was created a C.B. in William IV's Coronation Honours. Prior to his retirement from the Army in 1855, Lillie was a Lieutenant-Colonel in the Grenadier Guards. Interestingly, back in 1812, with Lieutenant-Colonel William Mayne, he had co-authored the Narrative of the Campaigns of the Loyal Lusitanian Legion.