"You have given me a strong and clear mandate — to make Quebec a country," he said to rapturous applause after he had been declared the winner.
Earlier, before the vote results were announced, Peladeau said much the same to the crowd.
"I have met, seen, heard and listened to men and women who believe, more than ever, that Quebec must become a country," he said.
"And that is great because I think the same thing."
Peladeau, 53, won 57.6 per cent of the vote, compared with 29.2 per cent for Alexandre Cloutier and 13.2 per cent for Martine Ouellet.
The winner required at least 50 per cent.
Peladeau's lofty objective of nationhood will have to wait at least for more than three years because the next election will be held only in the fall of 2018.
Despite his repeated pro-independence proclamations, Peladeau's stance on a sovereignty referendum is that he will wait to see what happens in the next election before deciding whether to hold one.
While much can change in three years, Peladeau looks as though he is facing a tough task on the referendum front. Opinion polls have consistently suggested that a majority of Quebecers are not interested in a third plebiscite, after those in 1980 and 1995.
Peladeau acknowledged that a lot of work lies ahead as he appealed to pro-nationalist forces to rally around one another.
"It is in all our interests to place the superior interest of Quebec above our personal ambitions," he said.
"The great coalition for independence must be reborn.
"I would like to tell the hundreds, the thousands of sovereigntists and nationalists who have left our party that all the projects of society will be possible once we have only one state and we are entirely masters of our destiny."
Of much interest will be Peladeau's reaction to being in the public eye on a constant basis.
His critics and political opponents say he is divisive, anti-union and too short-tempered to handle the frustrations and nuances of political life.
Peladeau also took the highly unusual step, for a PQ leader, of addressing party members in English on Friday night.
They were not the target.
"As the new leader of the Parti Quebecois, I would like to say to all our friends in North America and in the world, after all those decades and centuries, always in full respect for democracy and the rule of law, that we want to have and enjoy our own country," he said.
"And we want to position our people with the greatest opportunities and we want to live happy and peacefully.
"Our project is not against anyone or anything. Our project is not against Canadians. It's for the people of Quebec.
"It's for all citizens who believe in our capacity to live according to our best interests, to protect our culture and to flourish in this new world of the 21st century. I want all to be part of this great and legitimate objective."
Much of the leadership campaign focused on Peladeau's refusal to sell his shares in Quebecor Inc. (TSX:QBR.B), the conglomerate in which he remains the controlling shareholder. He promised to put the shares in a blind trust, a position critics say was inadequate.
The ongoing debate prompted Liberal house leader Jean-Marc Fournier to quip that if PQ members "want to transform the Parti Quebecois into the Parti Quebecor, it's up to them."
Although a political neophyte — he was elected in April 2014 — Peladeau's influence in Quebec is undeniable.
Quebecor owns some of the biggest media properties in the province such as newspapers, a TV network, book publishers and music distributors. His company is also a major player in cable, Internet and cellphone services.
Peladeau's passionate, public and fervent cries for Quebec sovereignty, coupled with his high profile, made him a seemingly irresistible candidate for party brass who long desperately to be pioneers of an independent country.
Stephane Bedard had been leading the PQ on an interim basis since Pauline Marois's resignation following the election defeat in 2014.
— Written by Donald McKenzie in Montreal