[3] His mother, Frances Clarissa Lombard, was descended from 17th century American colonists who had originated in Kent, England;[3] her father was a master shipbuilder.

[2] Some aspects of Clergue's early life are uncertain, and he may have studied engineering at the Maine State College of Agriculture and the Mechanic Arts, or taught school.

His schemes grew increasingly grandiose, as he promoted a variety of ventures in regions as far away as Alabama and Persia, and the scope of industries ranged from tourism, railways, public utilities, and shipbuilding.

[2] This included civic improvement projects in Bangor such street lighting and a street railway, a power station on the Penobscot River, an iron mine in Digby, Nova Scotia, a pulp mill, a foghorn manufacturing company, and new rail lines extending from Bangor into rural Maine; these ventures met with varying success.

The biographer Duncan McDowall remarks that "he possessed a knack for recognizing the potential of a new technology," but his ideas were often beyond practical possibility, and he lacked the technical knowledge and skills to implement them in realistic ways.

"[3] He committed extensive resources into developing tourism infrastructure on Mount Desert Island in Penobscot Bay in the Gulf of Maine, which by the 1880s was becoming a wealthy tourist enclave.

[3] Before the end of the decade, Clergue had moved on to even greater peaks of ambition when at the suggestion of Maine politician James G. Blaine, he sought to compete with British and Russian interests in Persia.

With the decline of Qajar Iran amidst the Great Game between these twin imperial powers, western financial and development interests began to encroach on the country.

Clergue made a bid for the long-term monopoly on banking, water utilities, and railways in Iran, but failed and had to return home in defeat.

Clergue initially planned to travel to Fort William, which commanded a strong position at the head of Lake Superior, to investigate the possibility of hydroelectric development.

Marie, which had water and rail transport connections, but had been bypassed by the Canadian Pacific Railway's transcontinental mainline a decade earlier, and whose economy had stagnated with the decline of the fur trade.

[3] Local businessmen had attempted a hydropower scheme intending to capitalize on the rapids of the St. Marys River, but a construction disaster left the project unfinished, with a debt load of $263,000 hanging over it.

Strategies like the National Policy championed by John A. Macdonald sought to grow Canada's manufacturing base and encourage immigration through exploitation of natural resources, and numerous financial incentives were available to industrialists and promoters who would contribute to an increase in settlement.

[3] Clergue's plan was to source the sulfurous acid needed for papermaking from Sudbury's nickel mining and smelting industry, but the dominant Canadian Copper Company declined any deal with him.

[5] In an industrial synergy, Clergue planned for the mines to give him two resources he desired: sulfur for his pulp and paper operations and nickel for steel-making.

[5] Captain of a fast-growing industrial empire that now employed 7,000 people,[3] Clergue was celebrated by boards of trade, politicians, and the media as having conquered the wilderness of Algoma, which until this point had been little impacted by European colonization.

[3] By September 1903, the Algoma mill had produced only 1,243 tons of steel rails and was unable to service the loans it had taken out the previous year, a large part of the debt being owed to the Speyer financial interests of New York City.

[8] Continuing to struggle during the Great Depression, in 1935 the Lake Superior Corporation came under the control of another industrialist, James Hamet Dunn, who once again salvaged and streamlined its operations to centre around Algoma Steel, which had become its flagship enterprise.

Clergue continued his work as an industrial promoter until his death, largely in a freelance consulting capacity,[3] and was Montreal-based for much of the rest of his life.

[3] Clergue died on January 19, 1939, in Montreal, and his remains were returned to the United States for burial at Mount Hope Cemetery in Bangor.