Loving v. Virginia (1967)
Mildred Jeter, a Black woman, and Richard Loving, a white man, were residents of Virginia where interracial marriage was barred by law.  They got married in 1958 in the District of Columbia .  When they returned to Virginia , they were arrested and sentenced to a year in prison for violating the ban.  The US Supreme Court unanimously overturned their conviction.  Stating that marriage was a basic civil right, the court ruled that "the freedom to marry, or not to marry, a person of another race resides with the individual and cannot be infringed by the State."

http://www.oyez.org/cases/1960-1969/1966/1966_395/