The enactment of antimiscegenation laws can be attributed to a variety of factors, including economic considerations and a desire on the part of some for the maintenance of so-called "racial purity." The first antimiscegenation statute appears to have been enacted in Maryland in 1661, in part for economic reasons. The statute forbidding interracial marriage in effect gave slave owners the ability to increase their number of slaves through birth. The statute deemed any child born of a free mother and slave father to be a slave of the father's master. The statute was designed to deter free white women from marrying black men. Before the statute, the freedom of a child was determined by her or his mother's free or enslaved status. If the mother was a free woman, the children would also be free. The 1661 statute changed this and increased the number of children born into slavery. The effect of the statute, however, was to increase forced interracial marriages because of the economic incentive for slave owners to force indentured white female servants to marry black male slaves to produce more slaves by birth from a slave father. Many other states in both the south and the north followed suit. America's first federal naturalization act, passed in 1790, limited the right to become citizens to "free white persons."Miscegenation is the intermarriage of people of different races. In the colonial United States the term is primarily used to describe the marriage between a black person and a white person.
Some states' antimiscegenation laws prohibited marriage between any races, but most laws were more concerned with preserving white racial purity. Many antimiscegenation laws were enacted at a time when slavery and notions of white supremacy had already become fixtures in the epic of American history. The notion of white supremacy and preserving "whiteness" encompassed the idea that marriage between races producing "mixed" children would "muddle" the purity of the white race. The "one drop rule" of classifying a person as black because the person had one drop of black blood exemplified the concern of some in the United States for preserving whiteness. To preserve white racial purity and prevent production of mixed offspring, many American states forbade the marriage between whites and blacks. This view was vindicated in the Supreme Court's opinion in Plessy v. Ferguson (1896), in which Homer A. Plessy, whose only non white ancestor was one of his eight great-grandparents, was determined to be black in the eyes of the law. Other states, such as California in 1909, added people of Japanese descent to the list of those banned from marrying whites.
Antimiscegenation laws remained in effect in many states from colonial days until 1967, when the Supreme Court declared Virginia's antimiscegenation law unconstitutional in Loving v. Virginia. The Supreme Court found that Virginia's law, which specifically prohibited and prevented the recognition of marriage between blacks and whites, denied citizens the fundamental right to marry. Soon after Loving v. Virginia was decided, most states repealed their own antimiscegenation statutes. Others kept these now unenforceable laws on their books, and some even kept the prohibition in their constitutions. The people of Alabama voted in November 2000 to remove the section of their constitution that prohibited interracial marriage. South Carolina took a similar step in 1998. While "mixed race" couples and their offspring continued to suffer Discrimination in the twenty-first century, no state is allowed to deny recognition of a marriage between a black person and a white person or between persons of any different races.