Remarkably, Coughlin had arrived in America a complete unknown less than a decade earlier. Raised in a religious family just across the Canadian border in Hamilton, Ontario, he was ordained in 1916 at the age of twenty-five. Coughlin was associated with the Basilian Order, which was sharply critical of the excesses of modern capitalism, particularly the sin of usury. The Basilian distaste for high finance stuck with him even after he left the order to become a parish priest in 1923.

Three years later, Coughlin took over a small congregation in the Royal Oak suburb of Detroit, and promptly built a new church. Deeply in debt to the diocese, he tried a variety of ways to raise money for his congregation. Nearing the end of his financial tether, he agreed to broadcast his sermons on WJR, a local station that was in equally dire straits.

Reading Coughlin’s sermons at a remove of eighty years, it’s difficult to see what all the fuss was about. His prose is stilted, repetitious, a bit leaden. But from the beginning Coughlin connected to listeners in an electric way. Part of his appeal, of course, was pure novelty. He was among the first to offer regular religious services over the air, and despite criticism from some within the church, he built the first true radio congregation.

Coughlin was also a master at identifying with the concerns and anxieties of his audience. He was emotional, dramatic, and evocative: the mother of a kidnapped child was having her heart crushed “in a great press, making her bleed the wine of sorrow.” The “purple poison of Bolshevism” was like “a great red serpent” winding its sinews around the American soul. And those who closed their eyes to these mounting dangers dwelled in “the smiling acres of Lotus Land where it is always afternoon, always springtime . . . dulled by the opiate of their own contentedness to such a degree that they possess no prospect of what the future years hold in store for our nation.”

But most of all, there was the voice. The novelist Wallace Stegner described it as a “voice of such mellow richness, such manly, heart-warming confidential intimacy, such emotional and ingratiating charm, that anyone tuning past it almost automatically returned to hear it again.” It was, Stegner wrote, “a voice made for promises.”

Though history now remembers Coughlin as among Roosevelt’s fiercest political foes, they began as close, if uneasy, allies. Having assailed Herbert Hoover and his gang of “international financiers” during the onset of the Great Depression, the priest looked more kindly upon Hoover’s successor. Throughout 1932 and 1933, he lavished fulsome praise upon FDR in his broadcasts and encouraged his listeners to do the same. It was “Roosevelt or ruin,” Coughlin declared on more than one occasion.

Yet Roosevelt remained wary of Coughlin. As he did with Huey Long, another potential threat to his presidency, Roosevelt maintained an outward cordiality with the priest, meeting with him occasionally and directing his staff to reply to the voluminous tips, suggestions, and notes Coughlin communicated to the White House. But Roosevelt’s private papers make clear that he saw the Detroit broadcaster as a demagogue, whom he genuinely disliked.

There was never a single decisive moment that shifted their relationship, but in the year following FDR’s election it became increasingly clear that Coughlin, despite his ratings clout, was not going to be invited into the president’s inner circle. By 1934 the frustrated priest’s ardor for the New Deal cooled, and anti-Roosevelt jibes began to creep into his broadcasts, as did an even more apocalyptic tone.

Douglas McCollam is a contributing editor to CJR.