Not so recently in the United States, same sex marriages were illegal. In the last century, there were laws on the books that prohibited folks from different races marrying.
Loving v. Virginia was a landmark civil rights case in 1967 that recognized marriage as a fundamental right guaranteed by the Fourteenth Amendment of the U.S. Constitution, which includes the Due Process Clause and the Equal Protection Clause.
In 1958, Mildred Loving, a Black woman, and Richard Loving, a white man, were convicted and sentenced to a year in prison for violating the state of Virginia’s laws prohibiting their marriage.
That conviction was overturned by the Supreme Court in 1968, ending discrimination in marriage based on race.