George Ferguson Bowen is said to have been born in Ireland on 2 November 1821, the eldest son of Edward Bowen, rector of Taughboyne, County Donegal. His mother's name is unknown. He was educated at Charterhouse, and won a scholarship to Trinity College, Oxford, where he was twice president of the union. In 1844 he graduated with first class honours in Classics and was elected a fellow of Brasenose College. He was appointed president of the University of Corfu in 1847 when he was in his mid 20s. In 1854 he became chief secretary of the Ionian Islands and was created CMG in 1855 and KCMG in 1856. He married Diamantine (Diamantina) du Romas, daughter of the president of the Ionian Senate, at Corfu, probably in 1856. There were four daughters and one son of the marriage. In 1859 he became the first governor of Queensland, Australia, and was created GCMG the following year. In 1867 he was appointed governor of New Zealand.
When Bowen took office on 5 February 1868, there existed 'a doubtful armed truce' between Māori and Pākehā in the North Island. The Colonial Office had concluded that the only way to cut costs and protect the Māori from overbearing treatment was to remove British troops, leaving the settlers with 'the full burden of their own defence' and responsibility for native policy. Governor George Grey, Bowen's predecessor, had defied imperial orders over the withdrawal of the regiments once too often and as a consequence his governorship had been terminated. Bowen inherited a ministry headed by Edward Stafford, who preached, but was reluctant to practise, military self-reliance. The colony's finances were stretched and the Armed Constabulary was not yet an effective fighting force. Nevertheless vulnerable settlements had been established on recently confiscated Māori land.
In mid 1868 Bowen received notice of the withdrawal of the one remaining British regiment. This news coincided with attacks on isolated settlements and military redoubts by Te Kooti in Poverty Bay and Tītokowaru in the Wanganui district. Bowen proclaimed his readiness to obey 'loyally and energetically' British orders to embark the 18th Royal Irish Regiment but he viewed its departure with alarm. He made impassioned appeals to the Colonial Office for the retention of the regiment, drawing parallels between the colony's situation and the Indian mutiny, the Irish rebellion, the Jacobite risings and even the fall of Rome. He gave lurid accounts of Māori hostility, lamenting the plight of settlers in threatened areas. At the same time he made much of the colony's expenditure on defence and Māori development. Above all he stressed the importance of a British garrison as a symbol of imperial authority. These outpourings caused Lord Granville, the secretary of state for the colonies, to doubt Bowen's suitability as governor.
Bowen's case was not helped by Stafford's attempts to retain the 18th Regiment without paying for its services. Stafford wanted Bowen to delay the departure of the troops on his own authority or, failing that, to shift responsibility for their removal onto the Colonial Office. Mindful of Grey's fall from favour, Bowen bluntly told Stafford that Britain could always find another governor who would willingly carry out the withdrawal policy. For all this, Bowen perhaps shares some responsibility for Commodore Rowley Lambert's decision in March 1869 not to embark the troops on the Himalaya. Stafford was succeeded by William Fox in June 1869. The Fox ministry appealed to Britain for military assistance, pledged payment, and asked for a guaranteed loan, but these requests were refused.
Colonial Office fears that Bowen, like Grey, was attempting to frustrate imperial policy were not justified. Although he was anxious to retain troops until the crisis had subsided, Bowen supported the British view that the colony would 'outlive' its Māori troubles as the disparity between European and Māori numbers increased. He urged moderate courses on his ministers, opposed further settlements on confiscated land and favoured a conciliatory policy towards the Māori King. Within a short time fears of a full-scale war subsided. Bowen played his part in the crisis of 1868–69, visiting Wanganui to encourage the beleaguered settlers, rallying pro-British tribes, and preaching racial reconciliation.
The rudeness with which Lord Granville had ruled out British assistance and advised the colony to rely on its own resources, provoked a crisis in Anglo-New Zealand relations. Colonists in London and New Zealand, in newspapers and the legislature, asserted that Britain was attempting to break up the Empire and accused the mother country of deserting New Zealand simply to save money. Some favoured secession and there was talk of seeking the protection of the United States. But events after the departure of the 18th Regiment in February 1870 showed that the danger was exaggerated. Good relations with Britain were restored after Granville apologised for some of his comments, the Treasury guaranteed a £1 million loan to aid economic recovery, and the conciliatory Lord Kimberley became secretary of state for the colonies. Bowen praised Kimberley for the 'completely altered tone' in dispatches, reminding him that 'national sympathy and not dry logic…keeps a great Empire together'.
While his ministers put Julius Vogel's development schemes into practice, Bowen went on numerous vice-regal progresses. He accompanied the Duke of Edinburgh, the Queen's second son and captain of the Galatea, on tours in 1869 and 1870–71, and visited the provinces, writing lengthy reports on their prospects. It is possible that Bowen's antipathy to Vogel influenced his decision not to invite him to form a ministry when Stafford was defeated in 1872 and G. M. Waterhouse resigned in 1873.
Bowen did his utmost to win the goodwill of the Māori. In 1870 he presented swords of honour from the Queen to Majors Te Keepa Te Rangihiwinui and Rāpata Wahawaha and several other chiefs for their services to the colonial cause. In 1872 he appointed Mōkena Kōhere and Wiremu Tako Ngātata to the Legislative Council, freed all Māori political prisoners and recommended a general amnesty. He supported Donald McLean's conciliatory native policy, and regularly visited Māori communities, hoping to reward loyalty and win allegiance. The Colonial Office considered that Bowen's 'tall' writing pleased the colonists and his 'palavers' with the Māori did much good, but Kimberley noted 'the very inflated style of Māori utterances which Sir G. Bowen naturally admires greatly and vainly endeavours to out do.'
Within the framework of responsible government the governor's position was that of a constitutional figurehead with limited discretion. Bowen served the Crown with dignity, generally obeyed orders, and accurately represented settler opinions in his dispatches. Aided by his wife, Diamantina Bowen, he made Government House a centre of social life and a neutral meeting place for politicians of different persuasions. He had his faults, in particular earning a reputation for pomposity. The Colonial Office wearied of his grandiloquent style, tediously developed historical comparisons and Classical allusions.
Bowen left New Zealand on 18 March 1873 to take up the governorship of Victoria, which he held until 1879. Subsequently he was the governor of Mauritius (1879–83) and Hong Kong (1883–87). His record of 28 years' continuous service as a British colonial governor was unequalled. In December 1887 Bowen was appointed chief of a royal commission to report on constitutional issues in Malta. Diamantina Bowen died in 1893 and he married, on 17 October 1896 in London, Letitia Florence White. Bowen died at Brighton on 21 February 1899.