[5] The impact of historical racial systems, such as that created by admixture between white European colonists and Native Americans, has often led people to identify or be classified by only one ethnicity, generally that of the culture in which they were raised.

In 2008, Barack Obama, who is of Luo (Kenyan) and Scottish lineage, was elected as the first biracial President of the United States; he acknowledges both sides of his family and identifies as African-American.

Several of the Thirteen Colonies passed laws in the 17th century that gave children the social status of their mother, according to the principle of partus sequitur ventrem, regardless of the father's race or citizenship.

(The practice of providing for the children was more common in French and Spanish colonies, where a class of free people of color developed who became educated and property owners.)

Interracial relationships have had a long history in North America and the United States, beginning with the intermixing of European explorers and soldiers, who took native women as companions.

They maintained these until forced to change in the 1960s and after by enforcement of federal legislation authorizing oversight of practices to protect the constitutional rights of African Americans and other minority citizens.

[23] In 1997, Greg Mayeda, a member of the board of directors person for the Hapa Issues Forum, attended a meeting regarding the new racial classifications for the 2000 U.S. Census.

[24]According to James P. Allen and Eugene Turner from California State University, Northridge, who analyzed the 2000 Census, most multiracial people identified as part white.

Despite a long history of miscegenation within the U.S. political territory and American continental landscape, advocacy for a unique social race classification to recognize direct, or recent, multiracial parentage did not begin until the 1970s.

After the Civil Rights Era and rapid integration of African-Americans into predominately European-American institutions and residential communities, it became more socially acceptable for White-identified women to date, marry and procreate children fathered by non-White men.

In 2009, Keith Bardwell, a justice of the peace in Robert, Louisiana, refused to officiate a wedding for an interracial couple and was summarily sued in federal court.

In June of that year, Lucas Vázquez de Ayllón established a Spanish colony near the mouth of the Pee Dee River in what is now eastern South Carolina.

In the early 19th century, the Native American woman Sacagawea, who would help translate for and guide the Lewis and Clark Expedition in the West, married the French-Canadian trapper Toussaint Charbonneau.

In the late 19th century, three European-American middle-class female teachers married Native American men they had met at Hampton Institute during the years when it ran its Indian program.

[95] In the late nineteenth century, Charles Eastman, a physician of Sioux and European ancestry who trained at Boston University, married Elaine Goodale, a European-American woman from New England.

His maternal grandfather was Seth Eastman, an artist and Army officer from New England, who had married a Sioux woman and had a daughter with her while stationed at Fort Snelling in Minnesota.

It is still most common in the United States (unlike some other countries with a history of slavery) for people seen as "African" in appearance to identify as or be classified solely as "Black" or "African-Americans", for cultural, social and familial reasons.

[100] The writer Sherrel W. Stewart's assertion that "most" African-Americans have significant Native American heritage,[101] is not supported by genetic researchers who have done extensive population mapping studies.

The critic Troy Duster, writing in The Chronicle of Higher Education, thought Gates' series African American Lives should have told people more about the limitations of genetic SNP testing.

[90] In their attempt to ensure white supremacy decades after emancipation, in the early 20th century, most southern states created laws based on the one-drop rule, defining as black persons with any known African ancestry.

This was a stricter interpretation than what had prevailed in the 19th century; it ignored the many mixed families in the state and went against commonly accepted social rules of judging a person by appearance and association.

[110][111] After the Civil War, racial segregation forced African Americans to share more of a common lot in society than they might have given widely varying ancestry, educational and economic levels.

[120] It's been recognized that grouping together all Afrodescent ethnicities, regardless of their unique ancestral circumstances, would deny the lingering effects of slavery within the American Colonial Era chattel slave descended community.

[122] Former Secretary of State Condoleezza Rice (who was famously mistaken for a "recent American immigrant" by French President Nicolas Sarkozy[123]), said "descendants of slaves did not get much of a head start, and I think you continue to see some of the effects of that."

[124] Some of the most notable[vague] families include the Van Salees,[86] Vanderbilts, Whitneys, Blacks,[125] Cheswells,[126] Newells,[127] Battises,[128] Bostons,[129] Eldings[130] of the North; the Staffords,[131] Gibsons,[132] Locklears, Pendarvises,[87] Driggers,[133][134] Galphins,[135] Fairfaxes,[136] Grinsteads (Greenstead, Grinsted and Grimsted),[137] Johnsons, Timrods, Darnalls of the South and the Picos,[138] Yturrias[139] and Bushes of the West.

... A person who is one-fourth or less American Indian or Korean or Filipino is not regarded as passing if he or she intermarries with and joins fully the life of the dominant community, so the minority ancestry need not be hidden...

But, most families of free people of color formed in Virginia before the American Revolution were the descendants of unions between white women and African men, who frequently worked and lived together in the looser conditions of the early colonial period.

[154] While interracial marriage was later prohibited, white men frequently took sexual advantage of slave women, and numerous generations of multiracial children were born.

By the late 1800s it had become common among African Americans to use passing to gain educational opportunities as did the first African-American graduate of Vassar College, Anita Florence Hemmings.

[192] According to James P. Allen and Eugene Turner from California State University, Northridge, by some calculations the largest part white biracial population is white/American Indian and Alaskan Native, at 7,015,017; followed by white/black at 737,492; then white/Asian at 727,197; and finally white/Native Hawaiian and other Pacific Islander at 125,628.