There will be no honeymoon for Pierre Karl Péladeau, the mercurial media tycoon who became leader of Quebec's separatist movement Friday night in a vote by Parti Québécois members.

It's not that Mr. Péladeau's victory in the PQ leadership was ever really in doubt – he won with 57.6-per-cent support. He had the most high-profile endorsements and on the ground his cheerleading supporters drowned out opponents at every event. Polls confirmed his dominance early on. Even before the results were announced, party delegates chanted "PKP! PKP!"

But PQ stalwarts watched the vote results in the provincial capital Friday night knowing questions about Mr. Péladeau's suitability for political leadership will only intensify now that he has dispensed with the two friendly rivals who challenged his leadership bid.

Story continues below advertisement

After an evening steeped in nostalgia for better times, with videos of past PQ victories and grainy ads from the 1970s, Mr. Péladeau also faces the daunting task of rebuilding a party described by former premier Jacques Parizeau as "standing before a field of ruin" after a disastrous 2014 election.

In his victory speech, Mr. Péladeau said the result is a great boost to "the final step in making Quebec a free country."

"You've given me a clear mandate to transform Quebec into a country," Mr. Péladeau said.

He described the result as an enormous vote of confidence, but the 43 per cent of votes that went to a weak field and the 20 per cent of members who did not vote illustrated the depth of divisions he must now try to heal.

Mr. Péladeau's character – mainly his quick temper and controlling leadership style – became an important issue to end the campaign but did not appear to put a dent in his support. The party clearly decided months ago it wanted to have its "PKP moment," as onetime leadership rival Jean-François Lisée said as he bowed out.

Mr. Lisée and another candidate who pulled out of the race, Pierre Céré, both said Mr. Péladeau's status as controlling shareholder of the Quebecor Inc. media empire is incompatible with his political ambitions. The two remaining candidates who went down to defeat Friday, Martine Ouellet and Alexandre Cloutier, did not make a big fuss about the issue.

Both were gracious in defeat, urging party faithful to rally to the new leader. "I'm going to work for the unity of our great political movement," Mr. Cloutier said.

Story continues below advertisement

Liberal House Leader Jean-Marc Fournier said the PQ is at risk of becoming the "Parti Québecor" with Mr. Péladeau at the helm.

In a little more than a week, a legislative committee will begin a review of ethics rules, parts of which will aim squarely at Mr. Péladeau's status as the dominant private media owner who is now positioned to be one of the main contestants for premier when the next election rolls around in three years.

Also, Mr. Péladeau must move quickly to create a so-called blind trust to manage his majority voting stake in Quebecor Inc. on his behalf to attempt to assuage concerns his media holdings will be placed in the service of his political ends.

However, Mr. Péladeau's plan to create the trust – with the large caveat that those shares must not be sold – threatens to fall short of the National Assembly's ethical standards for a premier. Claude Bisson, the former chief judge of Quebec who advises the assembly on legal issues, gave a legal opinion to the committee that will study an ethics update for MNAs that such a plan would be "incompatible with the very essence of a blind trust."

Nothing in current law can force an opposition leader to sell his holdings or to put them in a true blind trust, but political pressure has mounted as Mr. Péladeau's continued influence on the company has become clearer.

The Globe and Mail reported last week that the company tried to create a firewall between company and the controlling shareholder and former CEO immediately after he declared his candidacy for a seat in the 2014 election.

Story continues below advertisement

Mr. Péladeau angrily vetoed attempts to cut him off from Quebecor offices and e-mail, and the CEO who replaced him, Robert Dépatie, was gone within weeks citing health reasons.

Last week, current board chair Brian Mulroney said Mr. Péladeau would be consulted on important decisions involving the company such as major acquisitions or asset sales. His statement was nearly a year after the company said Mr. Péladeau would have no active role.

Other stories have emerged of Mr. Péladeau angrily confronting leadership and corporate rivals who have had a critical word or have otherwise showed disloyalty.

The gentle leadership race was the easy part for Mr. Péladeau, who must now show he has the political skill to unite the party and absorb critique with serenity instead of anger.