The 1990s (often referred and shortened to as "the '90s" or "the Nineties") was the decade that began on 1 January 1990, and ended on 31 December 1999. Known as the "post-Cold War decade", the 1990s were culturally imagined as the period from the Revolutions of 1989 until the September 11 attacks in 2001. The dissolution of the Soviet Union marked the end of Russia's status as a superpower, the end of a multipolar world, and the rise of anti-Western sentiment. China was still recovering from a politically and economically turbulent period. This allowed the US to emerge as the world's sole superpower, creating relative peace and prosperity for many western countries. During this decade, the world population grew from 5.3 to 6.1 billion.

The decade saw greater attention to multiculturalism and advance of alternative media. Public education about safe sex curbed HIV in developed countries. Generation X bonded over musical tastes. Humor in television and film was marked by ironic self-references mixed with popular culture references.