William J. P. MacMillan

William Joseph Parnell MacMillan
File:William Macmillan.jpg
18th Premier of Prince Edward Island
In office October 14, 1933 – August 15, 1935
Monarch	George V
Lieutenant Governor	Charles Dalton George DesBrisay DeBlois
Preceded by	James D. Stewart
Succeeded by	Walter Lea
Leader of the Conservative/Progressive Conservative of Prince Edward Island
In office October 14, 1933 – June 26, 1950
Preceded by	James D. Stewart
Succeeded by	Reginald Bell
MLA (Councillor) for 5th Queens
In office July 26, 1923 – July 23, 1935
Preceded by	C. Gavan Duffy
Succeeded by	C. St. Clair Trainor
In office May 18, 1939 – May 25, 1955
Preceded by	C. St. Clair Trainor
Succeeded by	Alex MacIsaac
Personal details
Born	(1881-03-24)March 24, 1881 Clermont, Prince Edward Island
Died	Charlottetown, Prince Edward Island
Nationality	Canadian
Political party	Conservative/Progressive Conservative
Spouse(s)	Mary B. Macdonald (m. 1909) Letitia Macdonald (nee Roberts (m. 1922)
Children	Mary Dorothea, Catherine Bernadette, Joseph, Stephen, Nora, and Allan
Residence	Clermont, Prince Edward Island
Alma mater	Prince of Wales College McGill University
Occupation	physician and surgeon
Profession	Politician
Cabinet	Minister without Portfolio (1923–1927) Minister of Education (1931–1933) Minister of Public Health (1931–1935) Provincial Secretary-Treasurer (1933–1935)
Religion	Roman Catholic

William Joseph Parnell MacMillan (March 24, 1881 – December 7, 1957) was a physician and Prince Edward Island politician.

Born in Clermont, MacMillan was a graduate of Prince of Wales College and the McGill University Faculty of Medicine.

After running a medical practice for several years, MacMillan entered politics in 1923 winning a seat in the provincial legislative assembly as a Conservative. In 1932 he became the province's first minister of health and education. As minister he rebuilt Prince of Wales College and the Provincial Mental Hospital which had both been destroyed by fire. He also secured a Carnegie Foundation endowment that enabled the government to establish a provincial library system.

When James D. Stewart became ill, MacMillan served as acting premier and then became the 18th Premier when Stewart died in 1933. MacMillan's government implemented relief programs and increasing government spending to help dampen the impact of the Great Depression. Nevertheless, his government was swept from power in the 1935 election which saw the Liberals capture every seat in the legislature. He returned to the legislature in 1939 and remained leader of the Conservative Party until the late 1940s and a member of the legislature until he lost his seat in the 1955 election.

MacMillan was named the province's lieutenant governor on November 22, 1957 but died before being sworn in.