Were There Other African-American Presidents?

While watching the Obama concert at the Lincoln Memorial with friends, a friend remarked that Barack Obama was not the first Black President-elect. Most of the group laughed, thinking this guy has not gotten over the fact his candidate lose the election. The guy continued to pledge his case by quoting a N.Y. Times article that stated President Warren G. Harding had Black relatives. According to the April 8, 2008 article, Our First Black President?, infamous historian William Estabrook Chancellor helped assemble a controversial biographical portrait accusing President Warren Harding of covering up his family's "colored" past. According to the Chancellor's created family tree, Harding was the great-grandson of a black woman. Under the one-drop rule of American race relations, Chancellor claimed, the country had inadvertently elected its "first Negro president."

Alton Maddox Jr.'s November 15, 2008 column "Obama Not First U.S. President of African Ancestry" caused quite a stir with many white readers, on the Black Star News website. Maddox uses the works of Dr. Auset Bakhufu, David Coyle and the eminent journalist and historian J.A Rogers to assert that we've had several presidents who were off-springs of the "one drop rule." They include: Abraham Lincoln, Andrew Jackson, Calvin Coolidge, Warren G. Harding and Dwight Eisenhower.

First I researched the one drop rule. According to Wikipedia, the one-drop rule is a historical colloquial term in the United States that holds that a person with any trace of African ancestry is considered Black unless having an alternative non-white ancestry which he or she can claim, such as Native American, Asian, Arab, or Australian aboriginal. It developed most strongly out of the binary culture of long years of institutionalized slavery. The concept has been chiefly applied to those of black African ancestry. Before 1930, individuals of mixed European and African ancestry were usually classed as mulattoes, sometimes as Black and sometimes as white, depending on appearance. According to Madison Grant, The Passing of The Great Race, 1916, the cross between a white man and an Indian is an Indian; the cross between a white man and a negro is a negro; the cross between a white man and a Hindu is a Hindu; and the cross between any of the three European races and a Jew is a Jew." States often stopped worrying about ancestry at "the fourth degree" (3 x great-grandparents). There was a lot of controversy on the one drop rule that enough for another article.

African-Americans and European-Americans have been in contact, sometimes intimate, since 1619. Before that there were the Moors. According to Wikipedia, in the Spanish language, the term for Moors is moro; in Portuguese the word is mouro. There seems to have been some confusion about the relationship of the word moro/mouro to the word Moreno (which means tanned or dark or brown-skinned), both from Greek maúros, i.e. Black. The description Moors has referred to several historic and modern populations of Muslim (and earlier non-Muslim) people of Berber and Arab descent from North Africa, some of whom came to inhabit the Iberian Peninsula. The North Africans termed it Al Andalus, comprising most of what is now Spain and Portugal. A map of the area can be found at http://www.worldhistorymaps.info/. Although the Moors came to be associated with Muslims, the name Moor pre-dates Islam.

Looking at the Wikipedia page List of United States Presidents by genealogical relationship, there were many who could be Black by the one drop rule. If Warren Harding was Black, so were his cousins. I did a few associations:
Fourth cousins
John Adams and Millard Fillmore (three times removed)
John Quincy Adams and Calvin Coolidge (five times removed)
Millard Fillmore and George H. W. Bush (five times removed)
Millard Fillmore and George W. Bush (six times removed)

Fifth cousins
Millard Fillmore and Grover Cleveland (once removed)
James Garfield and William Taft (once removed)
John Quincy Adams and Millard Fillmore (twice removed)
Millard Fillmore and Warren Harding (twice removed)
John Quincy Adams and William Taft (four times removed)
Millard Fillmore and Herbert Hoover (four times removed)
Franklin Pierce and George H. W. Bush (four times removed)
Grover Cleveland and Gerald Ford (four times removed)
Millard Fillmore and Gerald Ford (five times removed

Eighth cousins
William Taft and Warren Harding (twice removed)

Ninth cousins
Warren Harding and Richard Nixon
Warren Harding and Jimmy Carter
Warren Harding and Gerald Ford (once removed)

Tenth cousins
Herbert Hoover and George H. W. Bush
Herbert Hoover and George W. Bush (once removed)
George W. Bush and Barack Obama (once removed)

In 1968, the Harding biographer Francis Russell offered an explanation: Harding's great-great-grandfather Amos told his descendants that he once caught a man killing his neighbor's apple trees and that the man started the rumor in retaliation - a rather weak story that Russell declined to endorse and that did not silence the mixed-blood rumors.

Molecular anthropologist Mark D. Shriver heads a group of nine population researchers at Penn State University who are going beyond the arbitrary "one drop of blood" rule to answer ancient questions about the family trees of the typical American "Black" and "white." In the average self-declared white American's family tree, there is only the equivalent of one Black out of every 128 ancestors, according to the ongoing research of molecular anthropologist Mark D. Shriver of Penn State University and his colleagues.

Resources:
http://blackstarnews.com/?c=125&a=5117
http://en.wikipedia.org/wiki/List_of_United_States_Presidents_by_genealogical_relationship
http://en.wikipedia.org/wiki/One-Drop_Rule
http://www.nytimes.com/2008/04/06/magazine/06wwln-essay-t.html
http://www.science.psu.edu/forensics/faculty/shriver.html