A 900-page trove of letters written by Warren G. Harding to his longtime mistress will be made available online by The Library of Congress later this month. 

The Washington Post reports that a 50-year seal placed on the letters by the Harding family will expire July 29. The letters were donated by the descendants of the 29th President to the library in 1972, eight years after they were sealed. 

The letters are written to Carrie Phillips, who began an extramarital affair with Harding in 1905, while he was Lieutenant Governor of Ohio. The affair continued while Harding served as a U.S. Senator, but had apparently ended by the time Harding was elected President in 1920. Harding died suddenly of an apparent heart attack three years later in San Francisco while on a Western tour.

Phillips died in 1960. The letters were discovered in a locked closet in her former home by an attorney shortly before her death. Despite the 50-year seal placed on the letters by the Harding family, the Post reports that bootlegged copies on microfilm made their way to a historical repository in Cleveland, where they were used by author James D. Robenalt in a 2009 book about the affair. 

The letters written by Harding describe a very unhappy marriage with his wife Florence, with the future president writing in 1913 that "there isn’t one iota of affection in my home relationship ... It is merely existence, necessary for appearance’s sake."

Earlier that year, Harding had advised Phillips to burn his letters to her. 

"[H]ave a fire, chuck 'em!" he writes. "Do. You must. If there is one impassioned one that appeals to you, keep it . . . chuck the extra pictures, letters and verses. They are too inflammable to keep."

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