At his disposal Lt General Outram had the following...
Her Majesty's 14th Light Dragoons 89
Scinde Horse 303
Total 392 sabres
Her Majesty's 64th Foot 704
Her Majesty's 78th Highlanders ... 830
23rd Regiment Native Infantry 749
26th Regiment Native Infantry 716
Light Battalion 920
Bombay Sappers and Miners 109
Madras Sappers and Miners 124
No.2 Light Field battery 176
3rd Troop Horse Artillery 166
From the British Indian Navy he had the ....
Feroze 10 gun paddle frigate. The flag ship, under Captain Rennie
Semiramis 8 gun paddle frigate
Comet 5 gun paddle gun boat
Victoria 4 gun paddle steamer
(Lady) Falkland 2 gun paddle steamer/ cutter
Assyria 2 gun river steamer
Planet 2 gun river steamer
(Busks Navys of the World) 1859
The troops were assembled and towed in transport ships by the steamers. Tragically, the expedition had been delayed starting by the suicide of two high ranking officers, but the expedition started up the Shatt al Arab on March 19, and 6 days later they were in sight of Mohumra.
Mohumra was going to be a tough nut to crack, already strongly fortified because of it´s position, and with extra work done recently. In his report Lt. General Outram decribes the fortifications...
"For some months past the Persians had been strengthening their position at Mohumra. Batteries had been erected of great strength, of solid earth, 20 feet thick, 18 feet high, with casemated embrasures, on the northern and southern points of the banks of the Karoon and Shat-ool Arab, where the two rivers join. These, with other earthworks armed with heavy ordnance, commanded the entire passnge of the latter river, and were so skillfullilly and judiciously placed, and so scientifically formed, as to sweep the whole stream, to the extent of the range of the guns, up and down the river, and across the opposite shore; indeed, everything that science could suggest,, and labour accomplish in the time, appeared to have been done by the enemy to effectually prevent any vessel passing up the river above their position: the banks, for many miles, were covered by dense date groves, affording the most perfect cover for riflemen ; and the opposite shore, being neutral territory (Turkish), was not available for the erection of counter batteries." (London Gazette).
To defend the city, the Persians under Prince Khauler Mirza, .....
"The Persian army, ascertained from credible report to amount to 13,000 men of all arms, with 30 guns
Cavalry, Irregulars ... 1,500
9 Regiments, Regulars, 700 each 6,300
Arabs and Bukbtiarees and Beloocuees 4,600
Lt. General Outam, London Gazette
British soldiers on campaign in Persia (from Outram and Havelock's Persian Campaign by Capt. G. Hunt 1858)
Outram at first considered a frontal assault by infantry, but the Persain batteries were so well sited that this was courting disaster. So he decided on a more prudent bombardment of the Southern battery, with his naval forces, 4 steamers and 2 war sloops, supported by a mortar battery on an island opposite the Northern battery.
"On the 24th instant, the steamers, with transport ships in tow, moved up the river to within three miles of the Southern Battery, opposite the Arab village of Hurteh; but, as some of the large ships shoaled on the way, and did not reach the rendezvous until after dark, I was obliged to defer the attack for another day.
During the night, a reconnoissance was made in a boat to ascertain the nature of the soil of an island west of, and immediately opposite, the Northern Battery, where I wished to erect a mortar battery; but, as it was found to be deep mud, I determined to place the mortars upon a raft: this was constructed the following day, under the superintendence of Captain Rennie, I.N., and being armed with two 8-inch and two 5-inch mortars, with a party of artillery under Captain Worgan, was towed by the steamer Comet, and moored in position close to the island during the night, unobserved by the enemy, who, from our preparations at the rendezvous, and their confidence as to the impossibility of any vessel being able to pass above their batteries, apparently expected we should land on the southern island (Abadan).
The horses and guns of the artillery, a portion of the cavalry, and the infantry, were transshipped into boats and small steamers during' the day, in readiness for landing the following morning."
One steamer, the SS Hugh Lindsay of the Bengal Marine, had been fitted with carronades which were to be manned by the Madras Engineers and men of the 64th.
"At break of day, on the 26th, the mortars opened their fire upon both the Northern and Southern Batteries. The range of the 5 inch proved top short, but the 8 inch shells were very efficient, bursting immediately over and inside the enemy's works ; whilst, from the position of the raft, but few of the Persian guns could be brought to bear upon the mortars.
At seven o'clock, the several vessels of war moved up into the positions allotted them by Commodore Young, and, by nine o'clock, the fire of the heavy batteries was so reduced that the small steamers, with boats in tow, and one large steamer, the Pottinger, towing the transport Golden Era, were able to pass up and land the troops above the Northern Battery without a single casualty amongst the troops, although they had to run the gauntlet of both gun and musket fire; two or three native followers only were killed, in consequence of their unnecessarily exposing themselves.
By half-past one o'clock the troops were landed and formed, and advanced without delay through the date groves and across the plain, upon the entrenched camp of the enemy, who, without waiting for our approach, fled precipitately, after exploding their largest magazine, leaving, as I have before stated, their tents and baggage, public and private stores, with several magazines of ammunition and seventeen guns, behind. The want of cavalry prevented my pursuing them asI could have wished; but I despatched a party of Scinde Irregular Horse, under Captain Malcolm Green, to follow them up for some distance. This officer reported that he came upon their rear guard, retiring in good order, but that the road in many places was strewed with property and equipmonts. The loss of the Persians has been estimated at 200 killed, among whom was an officer of rank and estimation, Brigadier Agha Jan Khan, who fell in the Northern Battery."
The Persian garrison under Khanlar Mirza withdrew "in a very disorganized state" 100 miles north to the city of Ahvaz, leaving the British to enter Mohumra on March 29th, and promptly set about destroying the Persian batteries.General Outram organised a task force to proceed up to Ahwaz.