Victory in Toronto means Canada are assured of finishing in one of the top three places in the final stage of Concacaf qualifying for Qatar 2022.
Their last World Cup appearance came at Mexico 1986, where they finished bottom of their group without scoring.
Cyle Larin and Tajon Buchanan put Canada 2-0 up at half-time before Junior Hoilett and an Adrian Mariappa own goal sealed the victory.
It led to joyous celebrations from the sell-out crowd at BMO Field as Canada clinched World Cup qualification for only the second time.
English coach John Herdman, who led the Canadian women’s team to successive Olympic bronze medals in 2012 and 2016, has guided Les Rouges to Qatar in his first qualifying campaign in charge.
“We just qualified for the World Cup, this is a legit football country,” said Herdman, who last worked in England as an academy coach at Sunderland more than 20 years ago.
“When I first took over and I said, ‘We’re going to qualify for the World Cup’, I don’t think they believed us. I’m happy for them because all of these fans have waited and waited and waited, and hung in with us – and we’re going.
“I think this country never believed in us because we’ve given them nothing to believe in. They believe now.
“This is the time for everyone to get behind football and unite because we can be a powerhouse.”
The United States, Mexico, Costa Rica and Panama are all in contention for the final two automatic Concacaf qualification spots for the 2022 World Cup, which starts on 21 November.
Mexico and the US, who face El Salvador and Costa Rica respectively on Wednesday, need only a draw from their final qualification game to book their spots in Qatar.
Costa Rica, in fourth place, would need a big win against the US and for results to go their way to finish in the top three.
The fourth-placed country in the eight-team table earns a play-off against the winner of Wednesday’s final of Oceania qualifying between the Solomon Islands and New Zealand.