The argument for King's homosexuality has been put forward by biographer Jean Baker, supported by Shelley Ross, James W. Loewen, and Robert P. Watson, and focuses essentially on his close and intimate relationship with President James Buchanan.
The two men lived together for 13 years from 1840 until King's death in 1853.
Buchanan referred to the relationship as a "communion", and the two often attended official functions together.
Contemporaries also noted and commented upon the unusual closeness.
Andrew Jackson mockingly called them "Miss Nancy" and "Aunt Fancy" (the former being a 19th-century euphemism for an effeminate man), while Aaron V. Brown referred to King as Buchanan's "better half".
However, Lewis Saum, has argued that "…Customs and expressions were different in the mid-1800s than they are today...  "Miss Nancy" was "a fairly common designation for people who wore clean clothes and had good manners"; and noted that Aaron Brown was a political enemy of King.

Loewen has described Buchanan and King as "siamese twins".
A biographer of James Knox Polk, Barzman wrote that "King's "fastidious habits and conspicuous intimacy with the bachelor Buchanan gave rise to some cruel jibes."
Buchanan adopted King's mannerisms and romanticised view of southern culture.
Both had strong political ambitions and in 1844 they planned to run as president and vice president.
Both men were soft, effeminate and eccentric.
They spent some time apart while King was on overseas missions in France, and their letters remain cryptic, avoiding revealing any personal feelings at all.
In May 1844, Buchanan wrote to Cornelia Roosevelt, "I am now 'solitary and alone,' having no companion in the house with me.
I have gone a wooing to several gentlemen, but have not succeeded with any one 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."
After King died in 1853 Buchanan described him as "among the best, the purest and most consistent public men I have known."
 Baker concluded that while some of their correspondence were destroyed by family members, the length and intimacy of surviving letters illustrate "the affection of a special friendship" between King and Buchanan, with no way to know for certain whether it was a romantic relationship.
The argument for King's homosexuality has been put forward by biographer Jean Baker, supported by Shelley Ross, James W. Loewen, and Robert P. Watson, and focuses essentially on his close and intimate relationship with President James Buchanan. The two men lived together for 13 years from 1840 until King's death in 1853. Buchanan referred to the relationship as a "communion", and the two often attended official functions together. Contemporaries also noted and commented upon the unusual closeness. Andrew Jackson mockingly called them "Miss Nancy" and "Aunt Fancy" (the former being a 19th-century euphemism for an effeminate man), while Aaron V. Brown referred to King as Buchanan's "better half". However, Lewis Saum, has argued that "…Customs and expressions were different in the mid-1800s than they are today...  "Miss Nancy" was "a fairly common designation for people who wore clean clothes and had good manners"; and noted that Aaron Brown was a political enemy of King.
Loewen has described Buchanan and King as "siamese twins". A biographer of James Knox Polk, Barzman wrote that "King's "fastidious habits and conspicuous intimacy with the bachelor Buchanan gave rise to some cruel jibes." Buchanan adopted King's mannerisms and romanticised view of southern culture. Both had strong political ambitions and in 1844 they planned to run as president and vice president. Both men were soft, effeminate and eccentric. They spent some time apart while King was on overseas missions in France, and their letters remain cryptic, avoiding revealing any personal feelings at all. In May 1844, Buchanan wrote to Cornelia Roosevelt, "I am now 'solitary and alone,' having no companion in the house with me. I have gone a wooing to several gentlemen, but have not succeeded with any one 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." After King died in 1853 Buchanan described him as "among the best, the purest and most consistent public men I have known."  Baker concluded that while some of their correspondence were destroyed by family members, the length and intimacy of surviving letters illustrate "the affection of a special friendship" between King and Buchanan, with no way to know for certain whether it was a romantic relationship.
William R. King