MONTREAL -- Claude Castonguay, the Quebec politician known as the father of the province's public healthcare system and a mastermind of the Quiet Revolution, has died at age 91, according to media reports.

Castonguay, along with Jacques Parizeau, Michel Belanger and Claude Morin, was one of the main architects of the Quiet Revolution, the social movement that transformed Quebec during the 1960s. In his autobiography, titled 'Memoire d'un revolutionnaire tranquille,' Castonguay said he was “deeply convinced that social insurance is an essential element in any society oriented towards balanced economic and human development.”

To that end, he played an important role in the creation of Quebec's rental board system and the Caisse de Depot, before chairing a small committee that brainstormed on how the provincial government would adopt a health insurance program larger than the hospital insurance system that was then in place.

The defeat of Premier Jean Lesage in the 1966 election did not end Castonguay's career, as successor Daniel Johnson asked him to continue his work as an advisor to the government. That same year, he made Castonguay the chairman of a commission into health and social welfare.

The commission's first report advocated for the creation of a universal health insurance system, but its recommendations were not acted on by Johnson or his successor, Jean-Jacques Bertrand. But Castonguay soon found himself recruited by Robert Bourassa to run as the Liberal candidate in the Louis-Hebert riding in the 1970 election. In his memoir, he called it “an unexpected opportunity... to implement the reports of the commission in which I had invested so much.”

Upon his election, Castonguay was appointed Minister of Health and Social Services. By June, the law on health insurance was adopted but negotiations with doctors were not easy. In his book, he called a ban on the overbilling of fees one of his proudest accomplishments.

During his tenure, he oversaw the passing of the Act Respecting Health Services and Social Services, which notably led to the creation of CLSCs and community health departments.

Having promised his family that his political career would be short, he announced he would not run in the 1964 election, though he later admitted he would have preferred to stay in service longer. While Bourassa once again tried to recruit him in 1976, Castonguay declined.

After Bourassa resigned following his 1976 defeat, Castonguay did explore seeking leadership of the Quebec Liberal Party, but gave up when Claude Ryan entered the fray.

In his business career, Castonguay joined La Laurentienne in 1976, where he played an important role in growing the insurance company in North American and around the world, notably by preparing a merger with Les Prevoyants du Canada. Six years after joining the company, he was given full management of it. Castonguary would later say his best move was purchasing what would become the Laurentian Bank in the 1980s.

He served on several boards of directors, including the University of Laval Hospital Centre and Universite de Montreal.

He returned to politics in 1990 when he was appointed to the Canadian Senate as a Progressive Conservative, but served for only two years. He came back to public life once again in 1994 as Jacques Parizeau entrusted him with the presidency of a committee of experts on medication insurance.

He had a long reputation as a strong Quebec nationalist, but upon his entry into the business world, was public in criticizing Bill 101, saying it “went too far and would have serious repercussions on our economic development.”

He voted 'No' in the 1980 referendum but remained silent on his vote in 1995, acknowleding “it would have been impossible for me to argue with credibility in favour of a 'No' to sovereignty after having argued for so many years that changes were taking place.”

Castonguay was appointed an Officer of the Order of Quebec in 1991 and a Grand Officer in 2014.