Longest-Serving Prime Minister.

By James W.J. Bowden

This article first appeared in the Spring 2026 edition of The Dorchester Review.

Image from the Spring 2026 cover.

I HAVE BEEN SAYING for ten years that Mackenzie King does not qualify as “Canada’s longest-serving prime minister,” contrary to scholarly belief, and nor does his tenure set the record as the longest-serving prime minister anywhere in the Commonwealth, whether that means only the fifteen Commonwealth Realms which recognize Charles III as King, or the international organization called the Commonwealth of Nations, which also includes many republics once part of the British Empire. Perhaps I now sound like Randy Quaid’s character in “Independence Day” when he exclaimed: “I’ve been sayin’ it. I’ve been sayin’ it for ten damn years! Ain’t I been sayin’ it? Huh? I’ve been sayin’ it!” But I hold out this faint hope that the main thrust of my first foray into this subject in the pages of this journal in 2015, and my larger article from 2020 will yet one day blast its way into Canadian historiography and end this myth about Mackenzie King once and for all. 

Origin of a Myth

The myth that King’s tenure made him not only the longest-serving prime minister in Canada, but also in the entire Commonwealth, originated with King himself. He obsessed over the question in his diaries throughout 1947 and 1948 as he became increasingly preoccupied with his own legacy. In January 1947, for instance, he wrote: 

Were I to continue in office until June 10, 1948, I would have completed 21 years in office and would also have exceeded Walpole’s record, which means not only the record in all parts of the world today, but a record as far as is known for all time thus far. 

King had resolved to cling to the premiership for a while longer not merely to satisfy himself, but to give Canada more prestige. On July 18, 1947, King confided to St. Laurent:

I would like to outdistance Walpole’s record, and this is not because of anything other than that I felt the people of Canada would like that honour to come to our country, and also I thought many of our friends in the Empire would be pleased to see one of our day and under a democratic regime, make that record. 

King then informed the whole cabinet of his plan on Sept. 11, 1947 and added that he would like to have led the Liberal Party for 29 years, too. By November 1947, King had expanded his declarations of prime ministerial longevity to his counterpart in the United Kingdom, claiming that he discussed with Clement Attlee and other ministers his “years of office and importance of having something done when I have outrun Walpole’s record.” According to Pickersgill and Forester, who edited the first published King diaries in the 1960s and ’70s, “Mackenzie King equalled Walpole’s record tenure of office as Prime Minister of April 20 [1948] and received a flood of congratulatory messages,” including a portrait of Sir Robert Walpole and a handwritten note from Attlee presented by Britain’s High Commissioner in Ottawa. The Globe and Mail corroborated that Attlee and others had congratulated King and that (Canada’s) House of Commons greeted him “with a great round of desk-thumping” on April 20, 1948.

King never acknowledged that Sir John A. Macdonald served as prime minister longer than he and mentioned Macdonald only in the context of the Conservative Succession Crisis of 1891-96. By the 1940s, everyone had forgotten about (or at least preferred to forget) the Province of Canada, which P.B. Waite and J.M.S. Careless did not bring back to a popular readership until the 1960s in the lead-up to the Centennial. 

C.P. Stacey perpetuated the myth in 1976 and opened his famous expedition plumbing the darkest depths of King’s psyche, A Very Double Life: The Private World of Mackenzie King, by describing him as “Prime Minister of Canada longer than anyone else has ever been.” Stacey then closed the introduction — the most substantive part of his mini character assassination — by describing King as the longest-serving prime minister of any Commonwealth Realm:

Weakening health now forced King to think of retirement. In the summer of 1948, he completed twenty-one years as Prime Minister. In April he had passed the record supposedly set by Sir Robert Walpole and had held office longer than any other first minister in Commonwealth history; this gave him much simple pleasure. 

All is vanity, he might have added. Stacey discounted Sir John A. Macdonald as Canada’s longest-serving prime minister, even though the learned scholars of the 19th century, like Sir Alpheus Todd, counted Macdonald’s last ministry under the Province of Canada and his first under the Dominion of Canada as one and the same. 

Even excluding Macdonald’s first two co-premierships from 1856 to 1862, he served a total of 22 years and 26 days as prime minister between 1864 and his death in 1891, while King’s three ministries from 1921 to 1948 span only 21 years, 5 months, and 5 days. Counting all four of Macdonald’s ministries across the Province and Dominion pushes his total to 28 years and 22 days. 

“Prime Minister” and “Premier” were used interchangeably in Canada to describe the head of either a federal or provincial ministry until the mid-20th century; not until Bill Davis adopted the title of “Premier” instead of “Prime Minister of Ontario” in 1975 did the modern distinction between the federal Prime Minister and provincial Premiers solidify. What we today call provincial premiers in Canada and state premiers in Australia should also count in the calculation of the “longest-serving prime minister in the history of British Empire or Commonwealth” because federated polities also matter. 

Neither King nor Stacey thought so. King never mentioned the provincial premiers whose tenures had in 1948 surpassed his, and Stacey excluded the four long-serving premiers of Canadian provinces when he made that assertion in 1976. Sir Oliver Mowat’s premiership of Ontario lasted 23 years, 8 months, and 27 days in one unbroken ministry from 1872 to 1896. George Murray started his uninterrupted ministry as Premier of Nova Scotia in 1896 and remained in office for 26 years, 6 months, and 5 days until 1923. Ernest Manning served as Premier of Alberta for 25 years, 6 months, and 14 days from 1943 to 1968, and Joey Smallwood, who restored Responsible Government to Newfoundland and brought it into Confederation as the tenth province, dominated the Rock for 22 years, 9 months, and 18 days from 1949 to 1972.  

King had served as the longest Canadian prime minister since the arbitrary and ahistorical cutoff of Confederation. And if we excluded provincial premiers in Canada, then King himself in 1948 and Stacey in 1976 could have concluded that King also served the longest of any prime minister in the Commonwealth. But events would surpass King’s and Stacey’s declarations afterwards, and future historians in Canada failed to keep pace with these changes.

For example, Christopher Dummitt in 2017 pointed out: “For quite some time, it had been clear that Canada’s longest-serving prime minister was a rather odd duck.” In 2025, Barbara Messamore twice described Mackenzie King as “Canada’s longest-serving prime minister.” Also in 2025, Patrice Dutil praised King as “Canada’s longest-serving prime minister” and added that “no other person has held such office longer in the Commonwealth of Nations.” Dutil continued: “His closest rival in terms of prime ministerial tenure is Sir John A. Macdonald, who won six majorities, including four in a row, and who died in office just months into his last mandate.” Dutil discounted Macdonald’s co-premierships of the Province of Canada, even though his last ministry began in 1864 and carried over on July 1, 1867 before the first Dominion election in August-September 1867. Of course the Government of Canada echoes the myth: Parks Canada in 2024 lauded King as “Canada’s longest-serving prime minister with a record of achievements rivalled only by Laurier and Sir John A. Macdonald.” 

Not Even Second Place

“Canada” as a polity extends back to 1791 and not to 1867. The Imperial Parliament established Upper Canada and Lower Canada in 1791, continued and combined them into the Province of Canada in 1841, and then made the Dominion of Canada the direct continuator and successor polity to the Province of Canada in 1867. The Act of Union, 1841 and the British North America Act, 1867 each contain several provisions which expressly “continue” executive, legislative, and judicial authorities across the three iterations of this polity from 1791 to 1867. 

The eminent historians of the 19th century, such as Alpheus Todd, treated Macdonald’s uninterrupted time in office from 1864 to 1873 as one continuous ministry. The Governor General, Lord Monck, appointed Macdonald as Prime Minister of the Dominion of Canada in May 1867 even before the British North America Act, 1867 entered into force on July 1, because he was already the Co-Premier of the Province of Canada and a driving force behind Confederation. Almost all the cabinet was carried over as well, with the addition of some new ministers from New Brunswick and Nova Scotia. The Dominion’s first general elections in August-September 1867 gave the grouping led by Macdonald and Cartier a working majority in the House of Commons when the 1st Dominion Parliament met in November; consequently, Macdonald remained as Prime Minister. As Todd wrote in 1894:

Upon the confederation of the British North American provinces in 1867, Sir John A. Macdonald was appointed Premier (his ministry having already been in existence in the Province of Canada for three years); and he continued as prime minister until November 5, 1873, when the Mackenzie administration was formed. [. . .] In 1878 Sir John A. Macdonald returned to power, bringing with him most of his former colleagues, and remained in office until death removed him on June 6, 1891, having but one change of ministry in twenty-seven years.

For Todd, incidentally, “Prime Minister” and “Premier” were interchangeable. He so took for granted that the Province continued as the Dominion that he mentioned it as an innocuous aside, part of a larger argument in favour of ministerial by-elections, which supported stability in the executive in Canada, in contrast to the chaos and high turnover of ministries in the Australasian colonies that had not adopted this British practice. 

Todd cited 1864 as the inception of Macdonald’s cabinet so unostentatiously, almost in passing, because treating the Dominion of Canada as coterminous with the Province of Canada was obvious and uncontroversial. Sadly, what once seemed unremarkable to Todd’s generation had faded into obscurity by the mid-20th century.

Insisting that King served the longest as prime minister in the Commonwealth makes the omission of Sir John A. Macdonald even more damning. Even if you deny the place of the Province of Canada in Canadian history and the incontrovertible fact that it was the forerunner of the Dominion, you cannot deny its place in the history of the Empire and Commonwealth. 

King would only be the longest-serving prime minister of Canada if 1867 marks our Year Zero as almost all Canadian historians take for granted. King can claim the title only of Canada’s longest-serving prime minister since Confederation, but not of all time or in Canada. As Stacey himself pointed out, King’s tenure surpasses that of Sir Robert Walpole, the longest-serving British prime minister, and that of Sir Robert Menzies, the longest-serving Australian prime minister. The longest-serving New Zealand prime minister, Richard Seddon, does not even come close to King’s political longevity either.

Six Caribbean Rivals

Canadian historians have told themselves for so long that King served the longest of any prime minister in the Commonwealth, based on C.P. Stacey’s book and perhaps mere inertia, that they did not think to go back and check the historical record after 1976 to verify that the claim still holds up. It does not. Events have overtaken it.

The former British Crown colonies in the Pacific and Caribbean which achieved responsible government and gained independence as Commonwealth Realms in the 1960s, 1970s, and 1980s, also count. They, too, contribute to the history of the Commonwealth. Limiting the Empire and Commonwealth to the original interwar Dominions from 1931 erases our sister Realms in the Caribbean and Pacific altogether, even though five of them have already produced longer-serving Prime Ministers than King despite having achieved Responsible Government some 120 years after Canada. 

Since 1976, indeed, six Caribbean prime ministers have surpassed King’s tenure. Most recently, Keith Mitchell served as Prime Minister of Grenada, a Commonwealth Realm in the Antilles, in two terms from 1995 to 2008 and from 2013 to 2022 for a total of 22 years, four months, and 21 days. In 2025, Roosevelt Skerrit beat King’s record, having served as Prime Minister of Dominica, a parliamentary republic in the Commonwealth of Nations, since January 2004 for a total of 22 years as of Jan. 8, 2026.

Eric Williams served continuously as Chief Minister, Premier, and Prime Minister of Trinidad & Tobago from 1956 to 1981 for a total of 24 years, five months, and one day. (Trinidad &Tobago gained independence in 1962 as a Realm but became a parliamentary republic in 1976.) Lyndon Pindling’s unbroken tenure as Premier and Prime Minister of the Bahama Islands and as Prime Minister of the Commonwealth of The Bahamas from 1967 to 1992 lasted 25 years, seven months, and six days. George Cadle Price served as the First Minister and Premier of British Honduras and Prime Minister of Belize in two terms, first from 1961 to 1984, and again as Prime Minister of Belize from 1989 to 1993, for a total of 27 years, six months, and seventeen days. Finally, Sir Vere Bird served as Chief Minister and Premier of Antigua continuously from 1960 to 1971 and later as Prime Minister of Antigua and Barbuda from 1976 to 1994 for a total of 29 years, two months, and one day. He beat Sir John A. Macdonald’s record by one year. Both Belize and Antigua and Barbuda remain Commonwealth Realms in the personal union of Crowns of King Charles III and his heirs and successors. As the Province and Dominion of Canada form one polity in direct continuity, so, too, does Antigua relative to Antigua and Barbuda, and British Honduras with respect to Belize. In the history of all former British overseas territories, the hinge turns not on gaining full independence and international recognition but instead on assuming Responsible Government in local affairs. In Canada, that means 1841 (or 1848 at the latest), not 1867.

It is not a coincidence that four of these six men served as prime minister during their countries’ transitions from self-governing Crown colony to independent Commonwealth Realm. Macdonald’s premiership similarly straddles the transition of the Province of Canada into the Dominion, which also took on British Columbia, Prince Edward Island, and what are now Manitoba, Saskatchewan, Alberta, Yukon, Northwest Territories, and Nunavut under his tenure. His National Policy and Canadian Pacific Railway forged literal and economic east-west links that allowed this country to remain independent of the United States. Mackenzie King’s premiership likewise includes many milestones by which Canada accreted sovereignty and its own international legal personality in the interwar years, such as the Chanak Crisis of 1922, the Dominion Conference of 1926, the Abdication Crisis of 1936, the Royal Tour of 1939, and Canada’s separate declaration of war on Germany on September 10, 1939. Canada then emerged as a fully-fledged sovereign state after the Second World War and joined the United Nations in its own right in 1946, not as a sub-set of the British Empire. Joey Smallwood also restored Responsible Government to Newfoundland after it had given up its Dominion status in favour of rule by a Commission of British officials appointed in London. In the history of the British Empire, first ministers who lead their country to a new phase often end up staying on for a long time afterwards.

In an era when denigrating and unpersoning Sir John A. Macdonald has become fashionable, I hope that my fellow historians (if I may be so bold) will take note that Macdonald deserves the moniker of Canada’s longest-serving prime minister, because the Upper and Lower Canada of 1791, the Province of Canada of 1841, and the Dominion of Canada of 1867 form one unbroken line in British North America. We should keep our sister Realms in the Caribbean in mind, too, instead of overlooking their journeys to independence from the 1960s to the 1980s, and give their prime ministers their due. 

King’s Diaries at times show that his capacity for self-delusion knew no bounds, but let us not delude ourselves on his political longevity. And by the way, Sir Vere Bird of Antigua and Barbuda is the longest-serving Prime Minister of any liberal-democratic Commonwealth Realm — not Mackenzie King.

This article first appeared in the Spring 2026 edition of The Dorchester Review.

Notes

1. J.W.J. Bowden. “1791: The Birth of Canada.” The Dorchester Review 5:1 (2015), p. 28-32;
2. J.W. Pickersgill & D.F. Forester, The Mackenzie King Record, Volume IV, 1947-1948 (University of Toronto Press, 1970), 12.
3. Ibid., 60.
4. Ibid., 66.
5. Ibid., 106-107.
6. Ibid., 279.
7. Ibid., 280.
8. Globe and Mail, “Desk Thump for King as He Equals Record for Longevity in Office,” Apr. 21, 1949.
9. Pickersgill & Forester, loc. cit., 219.
10.  C.P. Stacey, A Very Double Life: The Private World of Mackenzie King (MacMillian, 1976), 9.
11.  Stacey, 31.
12.  Privy Council Office, “Twelfth Ministry,” “Fourteenth Ministry,” “Sixteenth Ministry,” in Guide to Canadian Ministries Since Confederation, 30 May 2025.
13.  J.O. Côté, ed., Political Appointments and Elections in the Province of Canada, 1841-1865, 2nd Ed (Ottawa: G. E. Desbarats, 1866), 30-35; Privy Council Office, “First Ministry,” “Third Ministry,” in Guide to Canadian Ministries Since Confederation, May 30, 2025.
14.  J.W.J. Bowden, “The Prime Minister of Ontario,” Parliamentum, Sept. 11, 2019.
15.  Christopher Dummitt, Unbuttoned: A History of Mackenzie King’s Secret Life (McGill-Queen’s University Press, 2017), 4.
16.  Barbara J. Messamore, Times of Transformation: The 1921 Canadian General Election (UBC Press, 2025), 24, 250.
17.  Patrice Dutil, The Enduring Riddle of Mackenzie King (UBC Press, 2025), 3.
18.  Dutil, 3.
19.  Parks Canada, Laurier House National Historic Site, “Political Life of William Lyon Mackenzie King,” Apr. 18, 2024.
20.  J.W.J. Bowden, “Canada’s Legal-Constitutional Continuity, 1791-1867,” JPPL 16, no. 2 (2020): 581-623.
21.  Alpheus Todd, Parliamentary Government in the British Colonies, 2nd ed. (Longmans, 1894), 62-63.
22.  J.W.J. Bowden. “1841: The Year of Responsible Government?” The Dorchester Review 6:2 (2016): p. 69-72.