William James Butler was born at Leamington, Warwickshire, England, on 18 March 1858, the son of Jane Matilda Long and her husband, James Butler, a master linen draper. His brother Joseph was born at Leamington on 1 March 1862. William sailed to New Zealand on the Atrato in 1874 with an older brother, Osmond. They cut firewood for a living at Kākahu in South Canterbury, where they were joined by Joseph. The three found work in a Southland sawmill in the early 1880s. There followed an unsuccessful stint prospecting for gold in Westland, after which William and Joseph worked for a time bridge building.
In the mid 1880s the two brothers began milling at Rimu in Westland; William worked as benchman and Joseph as tailer-out. The work was physically demanding and labour-intensive, but by 1892 they had accumulated enough capital to purchase a larger mill at Kōkiri, from which they began exporting to Australia. At Kōkiri they pioneered the use in New Zealand of a steam-powered log hauler, and in 1895 introduced a steam locomotive running on a wooden tramway. During this period Joseph also gained local recognition as a long-distance racing cyclist.
An indication of their wider interest in timber industry affairs came in 1896, when Joseph was a delegate to the Timber Conference called by Premier Richard Seddon to discuss government plans to legislate to conserve forests. He contributed a paper which attacked bitter competition and ruinous prices in the timber trade, and articulated the industry view that the forests were superabundant, conceding only that less wasteful utilisation was desirable.
The brothers sold their Kōkiri mill in 1902 and concentrated their attention on a new venture. The previous year they had set up the White Pine Company of New Zealand to mill kauri and kahikatea at Naumai on the Wairoa River, Northland. The kahikatea was all exported to Australia. The mill had water access only and profitability depended on a heavy investment in modern bandsaws and steam log haulers. Financial backing was provided by selling a half-share in the company.
In 1907 the Butlers sold their share to the Melbourne-based Kauri Timber Company and returned to Westland. After purchasing 28,000 acres of forest land at Ruatapu and Arahura from the Hokitika Harbour Board for £1 per acre, they were in the enviable and exceptional position of having long-term freehold timber supplies. A new company, Butler Brothers Limited, was set up, in which the Kauri Timber Company held a 40 per cent stake.
Both brothers had travelled to Canada and the USA in 1908 to study sawmilling techniques. On their return William reported on wood-pulp manufacture and in 1909 gave evidence before the Royal Commission on the Timber and Timber-Building Industries, condemning cheap timber imports from North America and refuting conservationist arguments. Joseph campaigned for the rights of sawmillers in evidence to the Royal Commission on Forestry in 1913. He pleaded for changes to the royalty system (whereby a royalty was paid to the Crown per foot of sawn timber) to encourage more efficient utilisation. He opposed plans for restricting kahikatea exports and, like William, rejected forest conservation: 'Nature having brought the forests to the highest point of utility, it is the duty of the community to utilize.'
In 1913, after a visit to Britain, Joseph was appointed to the board of directors of the Kauri Timber Company and moved to Auckland; soon after, he became New Zealand managing director. He was a board member of subsidiary companies, joined the Auckland Savage Club and was for three years president of the Auckland Club. He favoured increased tariffs to protect the local industry from North American timber imports in the 1920s, and this view led him into debate with the Auckland Chamber of Commerce which advocated free trade. In 1927 he became managing director of the Kauri Timber Company and shifted to Melbourne.
William remained director of Butler Brothers and several other sawmill companies. He was a justice of the peace, vice president of the Westland Chamber of Commerce and a member of the power board. His business philosophy was based on economic development and material progress, but his concerns were not merely pecuniary: he upheld the needs of the community as the end goal of industrial and commercial endeavours. He also disputed the view that state control was inevitably incompetent and unprofitable, and rejected competition where it created a duplication of public services as detrimental to the community.
In 1917 William was centrally involved in the incorporation of the Dominion Federated Sawmillers' Association, which brought together 75 mills. In drafting the new association's rules he emphasised co-operation in marketing and procuring supplies, as well as the protection and promotion of sawmilling interests. As first president of the association, a position he held until his death, he contested F. H. D. Bell's timber export restrictions, challenged the State Forest Service's introduction of stumpage tenders (a system of closed tendering on the value of standing timber), and endeavoured to protect the industry against imported timbers. He spent periods in Wellington lobbying ministers and appearing before select committees. His stance was often defensive and reactive: conditions in the industry were profitable for only two years between 1920 and 1932. However, his involvement with the Timber Industrial Efficiency Bill 1928 was an effort to co-operate with the state to reduce costs within the industry rather than regulate timber prices.
On 18 August 1898 at Reefton William Butler had married Janie McKenney, the daughter of a mine manager. There appear to have been no children. Joseph remained a bachelor all his life. During the first decades of the twentieth century the Butler brothers were the leading figures of the New Zealand timber industry. William Butler died at Wellington on 10 December 1932, survived by his wife Janie. Joseph died two years later in London, England, on 30 September 1934.