The breech-loading, single-shot .458in Martini-Henry rifle has become a symbol of both the Anglo-Zulu War of 1879 and the numerous battles in Egypt and the Sudan in 1884-85, but continued to be used by both British and colonial troops well into the 20th century. Its invention and introduction into British service were in direct response to the success of the Prussian Dreyse needle gun, which demonstrated that the breech-loading rifle offered faster loading, improved accuracy and superior range; significantly, the weapon could be loaded and fired from a prone position, thus offering the rifleman greater security on the battlefield.

The Martini-Henry first saw active service in the Ninth Cape Frontier War (1877-79), where it was particularly effective at stopping the charge of rebellious tribesmen at the battle of Centane. Indeed the success of the rifle bred a certain amount of complacency in the British Army that, armed with such a weapon, the British could repel any attack, even if seriously outnumbered. The British defeat at Zulu hands at Isandlwana dispelled this myth and it was only with the adoption of the square formation at Gingindlovu and Ulundi, with a corresponding concentration of fire, that the Martini-Henry really demonstrated its 'stopping power'. The same tactical formation and use of the Martini-Henry continued in the battles in Sudan in 1884-85. The Martini-Henry again showed its ability to stop charging warriors in the Second Afghan War (1878-80), particularly at the battle of Ahmed Khel, but against a force armed with modern weaponry, as at the defeat of Maiwand, the British Army did not fare as well. In 1888 the rifle was replaced in British service by the bolt-action, magazine-fed .303in Lee-Metford and Martini-Henry production ended in 1889, but it was to remain in service with colonial forces into World War I.

The Martini-Henry rifle was not without its faults or its critics. The rifle possessed a dreadful recoil when fired, especially once the bore was fouled, and in sustained combat severe bruising, even dislocation of shoulders and nose bleeds, were likely. The rifle had no safety mechanism of any sort and was prone to discharge if grit or sand entered the trigger mechanism. The weapon could jam, for the extractor grip might tear through the soft brass of the cartridge, or sand could enter the mechanism and cause a similar jam. The barrel became intensely hot when fired and although, from the Mk II design onwards, a wooden forestock was added to give some protection, the barrel would frequently become too hot to touch.

Despite these faults, the Martini-Henry Mk II was far superior to any firearm previously issued to the British Army. Its small bore - which meant soldiers could carry more ammunition - greater accuracy, lower trajectory, ease of operation and reloading with consequent rapidity of firing, as well as its robustness, all combined to make the Martini-Henry a solid, if not always completely dependable, weapon to be used against Britain's enemies. It was sighted to 1,000yd and could maintain a reasonable degree of accuracy at that range. The soft lead bullet could stop a charging warrior in his tracks, and in experienced hands ten to twelve 'aimed' volleys could be fired per minute into the charging ranks of a massed enemy.