The 2nd Battalion sailed on the Briton on 5th December 1899, and arrived at the Cape on the 20th after a very quick passage; was sent round to Durban on the Orcana, and joined the 10th Brigade under Major General Talbot Coke, two of whose battalions had been landed in Cape Colony, the two remaining with the general being the 2nd Dorsets and 2nd Middlesex. The 10th Brigade formed part of the Vth Division under General Warren, and went with him to Springfield and Venter's Spruit. The work of the brigade has been sketched under the 2nd Dorsets, and that of the Natal Army generally has been dealt with under the 2nd Queen's Royal West Surrey.
Like the Dorsets, the Somersets saw the heavy fighting between 20th and 24th January 1900 at Venter's Spruit and Spion Kop, but were not themselves seriously engaged. The Middlesex were on the summit all the afternoon of the 24th and lost heavily (see 2nd Royal Lancaster for account of Spion Kop).
On 21st February, during the last and successful attempt to relieve Ladysmith, the Somersets had their first heavy fighting among the hills north of Colenso. The country was very difficult, and the battalion seems to have got into a place where they were subjected to fire from three sides.
During the fourteen days' fighting the battalion's casualties were approximately 3 officers and 11 men killed, 1 officer and 80 men wounded. Five officers and 6 non-commissioned officers and men were mentioned in despatches by General Buller, 2 of the latter being recommended for the distinguished conduct medal.
After the relief of Ladysmith the Somersets left Coke's brigade and joined that of Major General Hart, which consisted of the Somersets, 1st Border Regiment, 1st Connaught Rangers, and 2nd Dublin Fusiliers, the first-named having taken the place of the Inniskilling Fusiliers, who were left in Natal. Hart's brigade was brought round to Cape Colony, and along with Barton's Fusilier Brigade was put under Sir Archibald Hunter as general of division. Hart's Brigade was ordered to Aliwal North to co-operate with Brabant in the relief of Wepener. The relief was accomplished on 24th April, and the brigade then followed Barton's to the western border. Having defeated the enemy at Rooidam on 5th May with the Fusilier Brigade, Sir Archibald Hunter proceeded to march through the Western Transvaal. One wing of the Somersets was left to garrison Vryburg, the other was taken east of Pretoria, and along with the 2nd Dublins formed the garrison of Heidelberg under Hart. On 26th July Major General Cooper with the 3rd King's Royal Rifles and 1st Rifle Brigade relieved Hart, who with the 2nd Dublins and half-battalion of the Somersets was ordered to Rhenoster, on the Bloemfontein-Pretoria Railway. He arrived there on the 30th, and marching to Kopje Alleen, joined Major General C E Knox and Major General Broadwood, who were endeavouring to surround De Wet. The Boer general with about 2000 men was then occupying the hills south of Reitzburg, near the Vaal. De Wet crossed the Vaal on the night of 6th August, and was at once pursued by several columns under the direction of Lord Kitchener, including that of Lord Methuen (see 1st Northumberland Fusiliers). De Wet escaped north of the Megaliesberg after some of his waggons, guns, etc, had been captured, and some prisoners he had with him had been released. In this pursuit Hart's men did 123 miles in the first seven days. After they were "whipped off" at Oliphant's Nek they went to help Hore at Elands River. Hart then moved into Krugersdorp about the middle of August. His column was shortly strengthened by the 2nd South Wales Borderers, 400 Imperial Yeomanry, and a 4'7 gun, and early in September he proceeded to Potchefstroom, having some fighting and extremely hard marching on the way. He then returned, reaching Krugersdorp on 30th September. During the march his column had disposed of a fair number of Boers, and had captured 96 prisoners, many cattle, waggons, etc.
After this the battalion was again taken to the Heidelberg district, and remained there a long time doing good work. In Lord Kitchener's despatch of 8th March 1901 Colonel Gallwey and two other officers were mentioned. On 25th May 1901 a convoy returning from Bethel to Standerton, the escort of which was a mixed force, under Colonel Gallwey of the Somersets, and including a portion of the battalion, was heavily attacked. "The escort fought with great gallantry and completely foiled the enemy's repeated attempts to press into close quarters". The Somersets lost 1 man killed and 3 wounded. Three officers and 6 non-commissioned officers and men of the battalion were mentioned in despatches for exceptional services that day, and the cause of mention after the name of Lieutenant and Quartermaster Moran is worth quoting: "Seeing party of enemy creeping up under cover of a donga, headed the cooks and invalids and drove them off". One can scarcely help associating cooks with kettles and invalids with crutches, but doubtless the gallant party left their impedimenta behind.
During 1901 a portion of the battalion did column work under Colonel E C Knox and other commanders in the north-east of Orange River Colony and the south of the Transvaal.
In Lord Roberts' final despatch 9 officers and 14 non-commissioned officers and men gained mention for good work up to the time the field-marshal left South Africa; and in Lord Kitchener's final despatch 3 officers and 3 non-commissioned officers were mentioned.