The corporation was initially established in 1958 to take over operations of the Star from the Atkinson Foundation after a provincial law banned charitable organizations from owning for-profit entities.

Torstar was founded after the Ontario government passed a law barring the provisions of late-Toronto Star owner Joseph Atkinson's will from being enacted.

The Progressive Conservative provincial government of George Drew passed a law banning charitable organizations from operating profitable entities such as newspapers.

Except for the Exeter Times-Advocate, St. Catharines Standard, Niagara Falls Review, Peterborough Examiner, and Welland Tribune, all acquired papers were to be closed.

[7][8] On December 20, 2018, Torstar applied to the Ontario Superior Court for an order to keep documents seized from its offices by the Competition Bureau sealed from the public.

[10] However, Torstar's share price had suffered from the company's inability to generate enough revenue or cost savings to pay quarterly dividends, which were suspended late in 2019.

[16] Grant Vingoe, chair of the Ontario Securities Commission, had previously said in a letter to Andrea Horvath that the court was the appropriate venue to challenge the proposal.

"[18] Late in the evening on July 27, an Ontario court approved the $60-million takeover of Torstar Corp. by private equity firm NordStar Capital LP over the objections of a rival bidding group, which immediately said it planned to appeal the judge's decision.

The division also owns The Hamilton Spectator, the Waterloo Region Record, the St. Catharines Standard, the Niagara Falls Review, the Welland Tribune, and the Peterborough Examiner.

The StarMetro chain of free daily newspapers serving Calgary, Edmonton, Halifax, Toronto, and Vancouver was also part of this division until publication of those titles ceased in 2019.

It was discontinued in late July 2017 after an investment totaling $20 million because of an inadequate volume of readers and advertisers and was replaced by universal apps available for both Android and iOS smartphones and tablets.