George Stoddart Whitmore was born on 30 May 1829 in Malta, the son of George St Vincent Whitmore and his wife, Isabella Maxwell Stoddart. His father was a lieutenant in the Royal Engineers stationed at Malta; his mother was the daughter of Sir John Stoddart, the chief justice of Malta. The Whitmore family had a tradition of military service. Whitmore's father died fairly young, with the rank of major, but three of his uncles and his grandfather became generals. George Stoddart Whitmore, destined for the army, was educated at Edinburgh Academy, Scotland, but his budding career took a curious turn when he was commissioned ensign, on 23 January 1847, in a South African colonial unit: the Cape Mounted Rifles. Whether his family wished to broaden his experience, save on the purchase of a regular commission, or correct some youthful indiscretion with temporary exile, is unknown.
Whitmore did well in South Africa. Under the eccentric but able command of General Sir Harry Smith, whom he admired, he participated in the 7th and 8th Kaffir wars in 1847 and 1850–53 against the formidable Xhosa and Khoisan peoples, and in the defeat of the Boers, at Boomplaats, on 29 August 1848. Promoted lieutenant on 21 May 1850 and repeatedly mentioned in dispatches, Whitmore revealed the organisational talent, courage, and physical endurance that were to become the most commendable of his traits. He also found time to join the Freemasons in 1850, and to meet and marry Eliza McGlocking, probably in 1851, at Boomplaats, South Africa. There were three children of the marriage, which ended with Eliza's death in the early 1860s. In 1854 Whitmore returned to England and was rewarded for his South African services on 7 July when he was made captain in the 62nd (Wiltshire) Regiment of Foot. With his connections, ability, and early experience of active service, Whitmore's prospects could hardly have been more hopeful.
In 1855–56 Whitmore served in the Crimean War against Russia. He was present at the siege of Sebastopol, where his regiment lost half its officers. Later he was commander of a unit of Turkish irregular cavalry (bashi-bazouks); and acted as a horse-buyer for the army in Austria–Hungary, Romania and, incognito, in Russia. He received a lesson in the importance of logistics, a brevet majorship on 6 June 1856, and the Turkish Order of the Medjidie (4th class, but some of his colleagues got 5th). In 1858 he attended the staff college at Aldershot, but ill health forced him to withdraw and take up a post as aide-de-camp to General William Eyre, who was commanding the forces in Canada. In 1860 he returned to the staff college and passed with the top mark for that year and one of the highest ever. Characteristically, he later implied that his thesis on the Waterloo campaign was plagiarised by Field Marshal Viscount Garnet Wolseley. In January 1861 Whitmore received the prized appointment of military secretary to Lieutenant General Duncan Cameron, who was leaving to assume command of the forces in New Zealand.
Cameron and Whitmore arrived in March 1861, to find a truce had been declared. After a year Cameron concluded there was little prospect of a renewal of the war, and resigned. Whitmore loyally followed suit. Cameron's resignation was rejected; Whitmore's was accepted. His promising military career had come to a halt.
In November 1861 Whitmore had acquired a large sheep run near Napier, in partnership with Captain J. C. McNeill, a fellow member of Cameron's staff. McNeill's cousin had managed the station, bombarded by detailed instructions from Whitmore. Now, Whitmore took over, selling his commission on 7 November 1862 and using the proceeds to improve his estate, which he had named Rissington, after a village close to the Whitmore home in Gloucestershire, England. Already an excellent judge of livestock and addicted to work – 'can't help doing it so long as I am here and it ought to be done' – he managed his estate with ruthless efficiency. He ran sheep and thoroughbred shorthorn cattle. His 'swell Bulls' were known throughout the colony and within a decade his estate comprised 110,000 acres, mostly leased. He later acquired the Clive Grange estate, but his freehold land was valued at only £3,290 in 1882.
Whitmore was appointed to the Legislative Council on 31 August 1863; he was civil commissioner for Ahuriri from March 1863 to September 1865, and commanded the Napier militia, as major, from 21 May 1863. Difficult to deal with, he was initially friendly with Donald McLean, but soon fell out with him and his closest associate, J. D. Ormond, who stands out from a very strong field as Whitmore's most bitter enemy. Local legend maintains that Whitmore repeatedly swindled his neighbours and partners, and he was certainly not above exploiting official position for private ends, but it seems improbable that he was unusually corrupt.
Renewed fighting with the Māori did break out in July 1863, and Whitmore attached himself as a volunteer to Cameron's staff. He witnessed the battles of Katikara and Ōrākau and led the colonial defence force in Hawke's Bay, but held no active command in the Waikato war. He visited England in 1865 and married Isabella Smith in London on 11 March. There were no children of the marriage.
From 1866 Whitmore at last became substantively involved in the New Zealand wars, leading the colonial forces in no fewer than seven distinct campaigns. As lieutenant colonel he led the Napier militia against an incursive Hauhau force, almost annihilating it at Ōmarunui on 12 October 1866. In July and August 1868 he organised the pursuit of Te Kooti inland from Poverty Bay. Despite difficult terrain, freezing weather and refractory troops, his own column caught Te Kooti at Ruakituri on 8 August, only to be defeated. Whitmore had been appointed commandant of the New Zealand Constabulary Force in early 1868. His rank was equivalent to lieutenant colonel. He fought his first two campaigns as a commander of local volunteers. In September the colonial forces met disaster in South Taranaki at the hands of Tītokowaru, and in the crisis Whitmore was promoted full colonel on 21 October 1868 and placed in charge of the main army, 1,000 strong. Hereafter he was, in effect, commander in chief.
Within two weeks Whitmore had restored order among the mutinous troops, but even so he was severely defeated by Tītokowaru at the hard-fought battle of Moturoa on 7 November. Leaving strong forces to contend with Tītokowaru, Whitmore then transferred his best troops to the East Coast and overcame great obstacles to take Te Kooti's stronghold of Ngātapa on 5 January 1869 with great slaughter, although Te Kooti himself escaped. Returning west, he led an army of 2,000 men against Tītokowaru's new pā, Tauranga-ika, but the decisive clash was averted when in early February 1869 the Māori forces disbanded because of internal dissension. Until early April Whitmore mounted a vigorous but unsuccessful pursuit of Tītokowaru through inland Taranaki. Whitmore's last and most difficult campaign was an ambitious invasion of Te Kooti's sanctuary, the Urewera district, from 4 to 18 May. Although Te Kooti again escaped, Whitmore undermined him by proving that the Urewera was not inviolable. Whitmore was eased out of his post in July 1869 by the new defence minister, Donald McLean, but received the CMG for his services, in December 1869. He was knighted in May 1882.
During these campaigns two of Whitmore's characteristics became pronounced. The first was his awesome capacity to inspire dislike. He was the prime target of James Hawthorne's A dark chapter in New Zealand history (1869), and the range of derogatory labels applied to him by others was impressive: 'contemptible little brute', 'great tyrant', 'chip of the Devil', 'inflated imbecile', 'miserable pretender', 'diminutive beast', 'little, conceited, egotistical…ass', 'perfect donkey without brains', to name a few. Some of this abuse stemmed from an incident during the Ruakituri campaign when, on 5 August 1868, Poverty Bay militia under his command refused to continue the expedition across the boundary of their own district. Whitmore had the defaulters dig their own graves preparatory to execution, and they begged on their knees for their lives. He later claimed he was joking – the only recorded jest of his entire life – but men like Hawthorne never forgave the humiliation. Whitmore was abused less fairly for being an extremely hard taskmaster, a physically tough man who imposed his standards on everyone else. However, it should be noted that, in addition, Whitmore was tactless, insensitive, arrogant, élitist and hypocritical.
Whitmore's second great characteristic was his immense military ability. His reputation is mistakenly seen to rest on Ōmarunui and his alleged annihilation of Te Kooti and Tītokowaru. In reality, the Hauhau force at Ōmarunui seems to have been only 80 strong, intent on evangelism rather than war. Whitmore defeated Te Kooti but he did not destroy him, and he neither defeated nor destroyed Tītokowaru. But it was Whitmore who conceived the strategy of rapidly switching the focus of operations from east to west and vice versa, exploiting the European monopoly of steamship transport. It was he who, in the Ngātapa and Urewera campaigns, deprived Te Kooti of a secure base and forced him to become the leader of a band of homeless fugitives. And it was he who converted the Armed Constabulary into a counter-insurgency corps comparable in type and quality to the French Foreign Legion. Several of Whitmore's campaigns were carried out in spite of quite staggering logistical difficulties and formidable Māori resistance. If the colonial 'self-reliant policy' ever had any meaning, it was in Whitmore's interpretation. That he condoned the massacre of prisoners at Ngātapa and the bounty hunting of heads during the pursuit of Tītokowaru is less creditable.
Whitmore's political career was secondary, but not insignificant. Except for a brief term representing Wairoa in the Hawke's Bay Provincial Council from 10 April 1867 until 29 May 1869, he wisely avoided elective office and sat secure in the Legislative Council for 40 years. He was colonial secretary from 18 October 1877 until 8 October 1879 in Sir George Grey's ministry, also holding the post of commissioner of the Armed Constabulary. For 10 days from 18 to 28 August 1884 he was a member of the Stout–Vogel ministry, but later quarrelled with Robert Stout. During the Russian invasion scares of the later 1880s, Whitmore was summoned from retirement and made commander of the defence forces. He was appointed major general on 4 December 1886, the first New Zealander to hold that rank. The Russians failed to arrive, and Whitmore resigned in January 1888. In the 1890s, despite his earlier support of liberal ministries, he defended large landowners in the Legislative Council, claiming that they were unfairly 'tormented' and 'perpetually attacked' for 'social pestism'. Towards the end of his life he visited England and while there suffered a stroke which partly paralysed him. He died in Napier on 16 March 1903 and was buried with Anglican rites at Napier cemetery. Premier Richard Seddon's eulogy arrived too late to be read.
Whitmore was a small man, trimly bearded, with a steely gaze. He constantly emphasised the importance of being 'a gentleman by birth and in manner', and kept his distance from military and civilian subordinates alike, except when reprimanding them, a task at which he excelled. Towards the Māori, he was contemptuous in theory and wary in practice. He wrote and talked incessantly but with considerable powers of analysis and expression: 'George [Duke] of Cambridge is a fool – Everybody knows he is – still he is an admirable Comd. [Commander] in Chief.' Whitmore's book, The last Māori war in New Zealand under the self-reliant policy (1902), is partisan but well written. Whitmore's personality weaknesses suggest he was embittered by a sense that fate alone had robbed him of a great career in the British Army. His strengths suggest that such a career may well have been possible.