In the sixties, Alex Trebek quickly became the go-to guy for hosting various TV shows for the CBC. These includes sports announcing, and Music Hop, a teen dance program that featured live musical performances — including, at one point, a young Gordon Lightfoot. 

His rise to game show host extraordinaire, though, seems to have begun when he was placed as the host of Reach for the Top, a quiz-themed program where teams of high schoolers would compete against other such teams, in various academic-themed challenges. By 1969, he was hosting another game show, Strategy. In this program, Trebek would stand in the middle of a circle, while contestants outside the circle would compete to navigate to him, in order to win products like a "clothes dryer" or a "freezer." 

Having proven himself on two smaller programs, in addition to all the previous work on variety shows and the news, Trebek was hired in 1970 to host Jackpot, a more prominent game show that ran on national Canadian television. This success propelled him into the U.S. media landscape, where in 1973 he hosted the U.S. game show The Wizard of Odds, a series wherein audience members were offered cash for answers related to statistical questions. This series only lasted a year, but Trebek rode on to another game show, High Rollers — which had contestants battle to wield giant pairs of dice — which he hosted for two years. In the latter half of the decade, he hosted The $128,000 Question, and started the eighties as the host of Pitfall.

Thus, by the time Merv Griffin revived the sixties trivia program Jeopardy!, in 1984, it's easy to see why he offered Trebek the coveted hosting position. With that wealth of experience, and that comfortable and confident demeanor, Trebek was a natural, and would go on to host Jeopardy! until his death. However, while Jeopardy! host would be the defining role of his career, he still occasionally took the opportunity to host other game shows from time to time, including Pillsbury Bake-Off (1994), and the famous occasion on April 1, 1997, according to Radio.com, when he and Pat Sajak, host of Wheel of Fortune, traded places as a prank.   

As for Jeopardy!, Trebek's final episode will air on Christmas Day, 2020.