Here’s what we know:

Warren G. Harding was the first sitting U.S. president to visit Canada. He did so on July 26, 1923, when he spoke to a crowd of 50,000 in Vancouver’s Stanley Park.

A week later, he was dead.

Here’s where the speculation begins:

To this day, no one can say with certainty how or why that came to be. Historical accounts agree that Harding had been in poor health before leaving on the cross-country tour that included his brief stay in Vancouver.

He had a history of heart problems. He had only recently gotten over the flu. And, while he was in Vancouver, he complained of nausea and abdominal pain.

Since an autopsy was never performed, rumours persist that Harding didn’t die of a heart attack -- as is commonly believed today -- or a stroke -- as was reported when he died -- but rather poison.

Some say he committed suicide, poisoning himself to avoid being tied to the scandals that plagued his administration.

Others say he was murdered, poisoned by his wife out of jealousy over his many extramarital affairs, or out of a desire to prevent his reputation from being ruined by the aforementioned scandals.

If preservation of reputation was indeed the goal of Harding’s supposed suicide or murder, it didn’t work. He’s generally regarded as one of the least-effective, most-corrupt presidents in U.S. history.

He was well-loved while in office, however, as evidenced by the thousands of mourners who turned up to watch the train that carried his body from San Francisco to Washington, D.C. as it rolled through their towns.

That love extended north of the border as well, where members of the Vancouver Kiwanis Club commissioned a memorial to him at the place in Stanley Park where he had spoken. He remains the only U.S. president commemorated in such a way in the city.