The affair between the future president and the wife of one of his best friends, dry-goods store operator James Phillips, began in August 1905 when Harding was lieutenant governor of Ohio and spanned his six years in the U.S. Senate before his landslide election to the White House in 1920. The newly unsealed letters, some of which are as long as 40 pages, date from 1910 onwards and abound with what Harding called “a mad, tender, devoted, ardent, eager, passion-wild, jealous…hungry…love” in one missive. “I love you more than all the world and have no hope of reward on earth or hereafter, so precious as that in your dear arms, in your thrilling lips, in your matchless breasts, in your incomparable embrace,” he wrote to his paramour on Christmas Eve in 1910.

Harding’s liaison offered a sexual outlet he didn’t have with his sickly wife, Florence, who suffered from chronic kidney issues. “There isn’t one iota of affection in my home relationship,” he wrote to Phillips in 1913. “It is merely existence, necessary for appearance’s sake.” Harding’s mistress, however, inspired him to compose verses such as these January 1912 stanzas:

“I love to suck
Your breath away
I love to cling —
There long to stay . . .

I love you garb’d
But naked more
Love your beauty
To thus adore . . .”

After Harding’s 1914 election to the Senate, the romance wasn’t the only thing heated between the pair—so was the growing debate about American entrance into World War I. Phillips had spent portions of three years in Berlin beginning in 1911 and developed a fervent pro-German stance. Although no solid proof has been found, some historians such as James Robenalt, author of the 2009 book “The Harding Affair: Love and Espionage During the Great War,” suspect that Phillips may even have been a German spy. Phillips pressed Harding to vote against sending American troops overseas, but love of country came first. “I have never approved of your war attitude, but I have loved you no less,” Harding wrote on March 12, 1915. “But I know as well as I live that you would not respect me, were my attitude different. I couldn’t be other than for my country, in the best way that I know to show my devotion.

As if the liaison wasn’t fraught with enough political danger, Phillips continued to advocate for the Germans even after the United States entered World War I on the other side. Harding grew increasingly concerned for the safety of his mistress, who was now under federal surveillance, and for his political future. “Please, I beg you, be prudent in talking to others,” he urged on February 17, 1918. “Remember, your country is in war, and things are not normal, and toleration is not universal, and justice is not always discriminating.”

Perhaps due to the disagreement over the war, the romance between the two became strained, and from Harding’s letters, it appears that Phillips may have threatened to reveal their relationship as Harding jockeyed for the Republican presidential nomination in 1920. “Your proposal to destroy me, and yourself in doing so, will only add to the ill we have already done,” he wrote in a February 2, 1920, letter in which he offered his mistress $5,000 a year for as long as he was in public service. A scurrilous 1922 Harding biography by William Estabrook Chancellor. speculated that the Republican National Committee paid for Phillips to take a lengthy trip to Japan with her husband in the months before the presidential election and provided her with up to $25,000 in return for her silence. “It’s really unclear if she ever cashed in on those letters or made any blackmail money,” Library of Congress archivist Karen Linn Femia said at an event last week.

What seems clear, though, is that the affair was over by the time the Hardings moved into the White House. Phillips, however, remained on good terms with the president. She received a ticket to the inauguration and visited the executive mansion with her husband and mother in 1922. The following year, Harding died suddenly in a San Francisco hotel room just 28 months into his term. Florence Harding passed away only 16 months later but was not left to rest in peace. Whispers had spread that the jealous first lady poisoned her husband in revenge for his infidelity, a scandalous claim given full throat by shady former FBI agent Gaston Means in his 1930 book “The Strange Death of President Harding.” The accusation had no basis in reality. “Harding for years had lived with extremely high blood pressure and heart disease,” Femia said. “There is no doubt that he died of natural causes.”

Presidential peccadilloes sometimes have the odd effect of making chief executives more popular, and some historians believe the love letters could actually improve Harding’s image. Then again, it couldn’t get much worse. Harding generally ranks near or at the bottom of presidents rated by historians and political scientists, and his administration was plagued by controversy, most notably the Teapot Dome scandal in which Interior Secretary Albert Fall was convicted of bribery.

The letters also counter a popular belief that Harding wasn’t articulate. “The passion to use plenty of words that sound well, and the totally inability to use them correctly is another trait’s of Warren’s,” Chancellor wrote in his biography. A newspaper editor by trade and a self-described “prosy lover,” Harding exhibited just the opposite in his letters that displayed both passion and a command of the language.

Harding’s decision to maintain his affair in spite of his paramour’s German ties also presaged problems of cronyism that plagued his administration. “It really was a political danger for him to continue the relationship with her,” Femia said. “He was very loyal, and that’s a characteristic that some people consider caused him problems in his administration, too much loyalty to some of his administration officials.”

Those letters wouldn’t be around for public consumption if Phillips had heeded Harding’s advice. “I have been thinking about all those letters you have. I think you [should] have a fire, chuck ’em!” he wrote on January 2, 1913. “They are too flammable to keep.” The existence of the indeed steamy letters did not become public until 1964, four years after the death of Harding’s mistress, at which time a probate court judge at the urging of Harding’s nephew sealed them for 50 years, a period that expired on July 29, 2014. The letters along with a collection of materials donated by the Phillips family are now available to the public at the Library of Congress and from its web site.

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