Born in Winchester, Hampshire, in England, he immigrated to Canada in his late twenties, settling first in Ontario and then in Alberta, where he farmed.

He was unable to control his caucus, which did not generally believe in party discipline, and his government almost lost several votes in the Legislature despite its majority.

He was unable to effectively address the problems facing farmers (including drought and low grain prices), bitter labour disputes in the coal industry, or the pronounced divisions in public opinion that had sprung up around prohibition (which his government ended).

Despite this, his time as Premier saw the elimination of the provincial deficit, substantial progress in negotiating the transfer of natural resource rights from the federal government, and the creation of the Alberta Wheat Pool.

By 1924, many UFA Members of the Legislative Assembly (MLAs) wanted to see Greenfield leave office, both because they were frustrated with his failings and because they thought it likely that a Greenfield-led government would be defeated in the next election.

After his retirement from politics, Greenfield represented Alberta in London, England, for several years before returning to Canada to work in the oil and gas industry.

He was elected to the local school board, where he spent twelve years, including stints as chair,[1] secretary, and treasurer.

[7] John E. Brownlee later said of Greenfield's involvement in the ALID that it was there "that he was first initiated into the discussion of public subjects, and it became the training ground for his subsequent success.

[1] When the UFA, which as part of its resistance to old-style politics had contested the election without designating a leader, won 38 of 61 seats, it found itself needing to form a government without having decided who would head it.

[11] However, Wood had little taste for the minutiae of government, preferring to remain at the head of what he saw as a broader political movement (saying he would "sooner be President of the UFA than the USA"),[11] and saw party lawyer Brownlee as the best choice.

[21] Many UFA backbenchers, however, wanted to see it repealed all together, but because of their objection to caucus discussions Greenfield was not aware of this by the time his amendments came to the floor of the legislature.

[23] Brownlee suggested that, in view of the legislators' inexperience with parliamentary procedure, the legislature consider the motion to adopt the bill on third reading as not yet having passed, that debate might ensue.

[23] More trouble with the legislature struck Greenfield in August 1922, during a special session called for the purpose of passing enabling legislation for a provincial wheat board.

[24] While Greenfield had hardly been the driving force behind the increases, he had facilitated them and had been blind to the appearance of paying MLAs more for six afternoons of work than some farmers were able to earn in a year.

[24] The grassroots of his own party condemned the move, all the more so when the wheat board that had been the purpose of the special session failed to come to fruition.

Greenfield was at a loss as to how to respond to this crisis, complaining that both employees and employers were the most difficult people in the province to deal with and that they showed "very little spirit of compromise".

[36] He tried to be balanced in his approach to this labour-employer friction but was not aided by his own Minister of Public Works, Labour MLA Alex Ross, who took the side of the miners and objected to the government's provision of police escorts for strikebreakers.

[36] Greenfield's own MLAs began to grumble about the policy—Archibald Matheson expressed in 1923 the view that "This government has acted as philosopher, guide, and God to the people long enough.

"[31] Public opinion, too, began to shift against the policy, more rapidly after 1922 when three police officers were killed in the line of duty by bootleggers.

[40] The last and most dramatic of these was the murder of Steve Lawson in front of the barracks where he and his family lived, by Emil "Pic" Picariello and Florence Lassandra.

[19] In both of these capacities, he was faced with a provincial deficit, which reached an accumulated total of $4 million between his taking office and the end of the 1922 fiscal year.

[31] This problem plagued Greenfield for his entire term as Premier, and it was not until Brownlee succeeded him that a resolution came in the form of a $25 million sale to the major lines.

[46] He found an ally in Richard Gavin Reid in 1923 when Greenfield, exhausted by his responsibilities, appointed the latter to replace him as Provincial Treasurer.

[49] Greenfield offered to stay, but on June 11 King told him that the cabinet would need the summer to consider the question and that no agreement would be immediately forthcoming.

[49] This decision did not help the Alberta Liberals, who went on to lose the next election soundly,[15] and did not prevent the transfer of resource rights, which took place in 1929,[50] but was enough to rob Greenfield of his glory; he left office the next year.

[51] At the UFA convention in 1923, a proponent of a provincial banking, George Bevington, made a passionate speech in favour of this idea, bringing most of the membership around to his side.

[33] Brownlee's opposition stemmed in part from investigations that Greenfield's government had already undertaken into the subject: information was gathered from similar experiments in New Zealand and New South Wales, leading to the conclusion that, while there would be some benefit to a provincially owned bank, Alberta "had neither the economic nor constitutional base to consider such a scheme".

[54] Against them stood Greenfield's government, UFA president Henry Wise Wood (whom Bevington was challenging for re-election),[54] and radical Labour Member of Parliament William Irvine.

[59] This time, Henry Wise Wood intervened to ask Brownlee to reconsider, which he agreed to do only if Greenfield himself made the request.

The Calgary Herald mocked the rebels as a "group of farmer politicians who have always claimed to be purer than those of other parties" and yet "[threw] their leader to the wolves in the hope that they may save their own skins".