Historical MapsLaws How America Achieved Full Marriage Equality June 26, 2015 Alex This post may contain affiliate links. As an Amazon Associate, we earn from qualifying purchases. The history of same-sex marriage in the US. In 2004 Massachusetts was the first state to legalize same-sex marriage. Related Posts:The Oldest Cities in the U.S. MappedThe Best World Atlases in 2025Map showing countries which since independence have…The Best World Map Posters In 2025Berries of North America MappedLegal Marriage Age for Girls by CountryWhich country has the most palm species?Government framework for gender equality