The most difficult task was that assigned to Wellesley, for he had to arrange for the security of an enormous tract of country, ruled over by chiefs whose friendship was more than doubtful. After providing for the defence of Guzerat, he left 2,000 men, including the 86th (Irish Rifles), near Baroda, a force of similar strength with the 65th (York and Lancaster) on the Taptee, and retained the rest for active operations under himself and Stevenson.
IV. Harcourt had with him for the advance through Cuttack the 80th Foot, two companies of the 22nd, and the 25th Light Dragoons, two regiments of Bengal cavalry, including a squadron of the Governor-General's Bodyguard, and four regiments of Bengal infantry.
The campaign opened with a simultaneous advance of all four armies, Lake moving on Ally-Ghur, Wellesley on Ahmadnagar, Stevenson on Broach, and Harcourt on Balasore.
On September 3 Lake stormed and carried the fortress of Ally-Ghur.
Ally-Ghur, September 3, 1803.
This battle honour is borne on the colours of the West Riding Regiment alone; no other corps which shared in that decisive victory being now existent; the two native regiments which bore such a gallant part in the storming of the fortress having been swept away during the Mutiny of 1857.
On the issue of the India General Service Medal in 1851 the survivors of this action were granted that medal, with a clasp inscribed "Ally-Ghur."
Ally-Ghur was held by a powerful force under the command of the Frenchman Perron, and it made a gallant defence. The troops selected for the assault were the 76th Foot, the 1st Battalion of the 4th and the 17th Native Infantry, under Colonel the Hon. G. Monson, the casualties being:
| Regiments. | Officers. | Men. | ||
| K. | W. | K. | W. | |
| 27th Lt. Drag. | - | - | - | 6 |
| Royal Artillery | - | 1 | 2 | 7 |
| 76th West Ridings | 6 | 4 | 19 | 62 |
| 4th Bengal Infantry | 1 | 4 | 20 | 84 |
| 17th Bengal Infantry | - | 2 | 8 | 36 |