As the only "bachelor president", many historians have speculated about the 15th president's sexual orientation. This speculation doesn't just stem from the fact that James Buchanan never married, but rather from his very close friendship with Alabama Senator (and later Vice-President) Rufus King and the openly affectionate correspondence that the two men carried on. One might easily dismiss this to the flowery literary style of of 19th century letter-writing, but Buchanan was also openly teased both in and out of earshot about his relationship with King, by some of the leading members of Congress, who suggested that King and Buchanan were a couple. Buchanan himself made some very curious statements about that relationship. Coincidentally, King was the only bachelor Vice-President, and even more coincidentally, both men instructed their families to burn the correspondence that passed between the two of them after their passing.

In 1819, Buchanan was engaged to Anne Coleman, the daughter of a Philadelphia millionaire. She broke off the engagement after an "outburst of hysterics" according to historian John Seigenthaler. There was some speculation that Buchanan was only marrying her for her money, and the bride-to-be's awareness of this may have been what caused her to call off the nuptials. Coleman died shortly thereafter, quite possibly a suicide according to Philip Klein, one of Buchanan's biographers. Her attending physician said that this was the first instance he had heard of where "hysteria produced death." The physician's records list her cause of death as an overdose of laudanum, an opiate. Seigenthaler writes: "her parents would not allow Buchanan to attend the funeral and his letter of sympathy was returned unopened by her father. Buchanan swore never to marry in honor of her memory."
While in Washington, Buchanan's "room-mate" was Senator Rufus King. The two men were virtually inseparable and were rumored to be lovers.They shared a house and a bedroom (this apparently was not uncommon for the time.) Many openly wrote about this and spoke this accusation. For example, Tennessee Governor Aaron Brown was sent to Washington as an advance man for President-Elect James K. Polk, and wrote to Polk describing King as Buchanan's "better half" and as "Aunt Nancy" (a 19th century derogatory term for gay men). Although Buchanan was unmarried, Brown writes to Polk: "General Saunders, in the presence of Mr. Buchanan and his wife and some others, advanced the opinion that neither Mr. Calhoun nor Mr. Van Buren had any chance to be elected...and being asked by someone, who then can be, he forgot himself and said that Colonel Polk could run better than any man in the nation. This of course was highly indecorous toward Mrs. B." Former President Andrew Jackson would also refer to Rufus King as "Miss Nancy" and "Aunt Fancy", both being derogatory terms for gay men in the 19th century.
Historian Robert Remini, a biographer of Henry Clay, writes that Clay "rarely missed an opportunity to mock Senator Buchanan" when the two were in the senate. He writes of an occasion when Clay said to Buchanan, "in a soft feminine voice": "I wish I had a more lady-like manner of expressing myself". Historian James Loewen supports the theory that Buchanan and King were lovers, noting that the two were referred to around Washington as "Siamese twins" which was another contemporary slang for gay couples. Professor Loewen goes so far as to speculate that Buchanan's affection for the southerner King may have been what influenced the Pennsylvanian to have such strong pro-slavery views.
In 1844, President Polk appointed King as Ambassador to France. King wrote Buchanan telling him "I hope you will find no one to replace me in affection." Buchanan later wrote to a female friend, a Mrs. Roosevelt, that "I am now solitary and alone having no companion in the house with me. I have gone wooing to several gentlemen but have not succeeded with any of them. I feel that it is not good for man to be alone, and I should not be astonished to find myself married to some old maid who can nurse me when I am sick, provide good dinners for me when I am well, and not expect from me any very ardent or romantic affection."
King also wrote with sadness of his separation from Buchanan. In a letter to Buchanan in 1844, King wrote "I am selfish enough to hope you will not be able to procure an associate who will cause you to feel no regret at our separation. For myself, I shall always feel lonely in the midst of Paris, for here I shall have no Friend with whom I can commune as with my own thoughts."

Buchanan and King's nieces destroyed their uncles' correspondence, leaving many to questions what type of relationship the two men had. In the final analysis though, it's all speculation. I was told by a member of this community that the staff at the Wheatland (the museum that was once Buchanan's home) get angry and bristle at the suggestion when asked if Buchanan was gay. One historian notes that "there have always been gay men and women throughout history, in all walks of life, so why not in Buchanan's time?" But perhaps the most accurate observation on the subject comes from Buchanan biographer Michael J. Birkner, who writes, "what we know would not give even the most adventurous psycho-biographer much to go on."