On 3 Feb 1816, India, Ramnager. A formal declaration of war by the Nepalese
1/66th, as part of the 2nd Brigade, reached here and waited ten days for the Commissariat.
As part of the 2nd Brigade, the 1/66th marched to Maha Jogee on 13 February and encamped. It passed the Nepalese frontier on 17th February
On 23 Feb 1816, Nepal, Rapti. 1/66th, as part of the 2nd Brigade, was in the open valley of the Rapti. Nepalese government signed the peace.
On 5 March the 1/66th sent to camp and, between the 8th and 28th March, marched back to Dinapore
On 27 Feb 1816, England, Portsmouth. Regiment embarked on 'Seringapatam' and 'Alexandra' transports for Ireland, the ships reaching Monkstown in Cork Harbour on 24 March. The next day it disembarked and marched to Cork, continuing the march, to Fermoy, on 27 March
On 3 May 1816, Ireland, Fermoy. Over the 3 - 5 May the Regiment left Fermoy in three divisions, arriving at Naas over 10 - 12 May. It started a march to Dublin over the 29 - 30 May, where it was quartered
On 3 July 1816, India, Dinapore. 1/66th started by boat up the Ganges. The 1/66th arrived at Cawnpore on 8 August, but no barracks were ready so they were kept on the boats. Finally installed in barracks on 20th August
On 19 Jan 1817, India, Cawnpore. 1/66th again embarked on the Ganges and reached Calcutta on 15th March, from where it embarked on 24 March for St Helena. Touched Mauritius and the Cape.
The 1/66th arrived at Jamestown from India on 5 July and joined the 2/66th there.
On 23 Jan 1817, Ireland. Headquarters of Regiment transferred to Nass and the Regiment scattered in small detachments at Athboy, Aughavagh, Drumgoff, Glencree, Goldmines, Kells, Killock, Laragh, Leitrim, Old Castle, Prosperous, Rathangan, Robertstown, Trim and Wicklow
During Mar 1817, Ireland. A very small detachment was deployed at Athy and Montaserevin. The detachment at Wicklow was withdrawn. The duties of these detachments had been to prevent mobs plundering trade Boats on the Grand Canal
On 1 May 1817, Ireland, Naas. Various detachments were relieved and marched back to Naas.
Some detachments were deployed to Ballynamull, to Callan and to Tullamore.
On 19 June 1817, Ireland, Waterford. Field Officer's detachment was deployed at Waterford, with smaller detachments deployed at Dungannon and New Geneva
On 25 June 1817, Ireland, Naas. By this date the Waterford and other detachments had been withdrawn and, the next day, detachments were deployed to Golden, Killemaul, Lyttleton, Mocckler's Hill and New Birmingham.
During August the Killemaul detachment was ordered to withdraw
On 10 Oct 1817, Ireland, Clonmel. Regiment deployed at Clonmel. During November detachments were withdrawn and Regiment assembled at Cork, from where detachments were deployed to Charles Fort and Monkstown
During 1818, Canada, Nova Scotia, Halifax. 1st Battalion remained here until 1819. During the year the Left Wing of the 1st Battalion left Bermuda to join the 62nd Regiment at Halifax
During May 1818, Ireland, Cork. The number of detachments increased, being deployed to Bantry, Bere Island, Bultevant, Charlesville, Clonakilty, Dingle, Mill Street, Rose Castle, Skibbereen, Tralee and Whiddy Island
On 9 Jan 1819, Ireland, Fermoy. Regiment Headquarters deployed here, with detachments deployed to Camden, Carlisle Fort, Kilworth, Middleton, Spike Island and Younghal