Final answer:
Anti-miscegenation laws were invalidated in 1967 by the Loving v. Virginia case. Starting in 1998, thirty states enacted laws or amendments against same-sex marriage, but the Supreme Court's Obergefell v. Hodges decision in 2015 made same-sex marriage legal across the United States.
Step-by-step explanation:
The history of marriage laws in the United States has seen significant changes, particularly in terms of legislation regarding interracial and same-sex marriages. Laws prohibiting interracial marriages, known as anti-miscegenation laws, were rendered unconstitutional by the U.S. Supreme Court in the landmark case of Loving v. Virginia in 1967. Thirty states passed amendments or laws against same-sex marriage between 1998 and 2012, though ultimately, the Supreme Court ruled in Obergefell v. Hodges in 2015 that state bans on same-sex marriage were unconstitutional, legalizing same-sex marriage nationwide.