The year 1991 is the year that grunge music made its popular breakthrough. Nirvana's Nevermind, led by the surprise hit single "Smells Like Teen Spirit", becomes the most popular U.S. album of the year. Followed immediately by other grunge bands like Pearl Jam, Alice in Chains, Soundgarden and in 1992 by Stone Temple Pilots, grunge dominates the U.S. charts for the next few years. Its success effectively ends the reign of the glam metal groups that enjoyed massive success in the 1980s like Mötley Crüe, Poison, Warrant, Cinderella, and Ratt whose sales and critical viability were beginning to decline for about two years previously. Even so, the rock band Guns N' Roses's popularity flourishes with the release of their albums Use Your Illusion I & Use Your Illusion II, both selling over 10 million copies each. Def Leppard's next album Adrenalize, released in March of 1992, would go on to reach multi-platinum status and prove to be the last major commercial success for 80's pop metal. A Tribe Called Quest's Low End Theory is released this year; it would go on to be considered one of the best hip hop albums of the 1990s. A Tribe Called Quest, along with De La Soul, Dream Warriors, Gang Starr and the Poor Righteous Teachers, help define what comes to be known as alternative rap with important releases this year.

On November 24 Both Kiss drummer Eric Carr and Queen frontman Freddie Mercury died. Mercury was at home in London on November 24, due to AIDS complications. Rumors had been circulating that Mercury had AIDS, but the death comes as a shock to millions of fans and the music industry. The remaining members of Queen form the Mercury Phoenix Trust and the following year, a tribute concert is staged in Wembley Stadium. A sell-out crowd in attendance witness the three surviving members reuniting to play along with performances by the likes of David Bowie, Elton John, Guns N' Roses, Def Leppard, Metallica, Annie Lennox, and George Michael.

Queen's "Bohemian Rhapsody" goes to number one for the second time in the U.K., which is the one of the only times a single has gone to number one in the same version more than once (another example is Chubby Checkers' "The Twist," which was #1 in 1960 & 1962). It is also the only time a single has gone to number one more than once on the UK Christmas charts. It has now spent a total of 14 weeks on top of the UK charts.

1991 is also the year CCM, or contemporary Christian music, reaches a new peak. Amy Grant, who had already crossed back and forth between CCM and pop in the mid-80s, achieves her first solo #1 hit on the pop charts with the hit single "Baby Baby," becoming the first single by a CCM artist to reach #1 (despite the fact the song was a pop song and was void of any Christian references). Another single, "That's What Love Is For," would also top the charts, this time in the Adult Contemporary field. Meanwhile, Grant's album Heart In Motion reaches #11 on the pop chart and #1 on the Christian chart despite its non-religious objective, and quickly becomes a best-seller. Another CCM crossover artist in 1991 is Michael W. Smith, who achieves a Top Ten pop hit with his single "Place In This World." The subsequent album, Go West Young Man, is also a hit.

The massive success of Garth Brooks in this year sets the stage for the mid-1990s influx of pop-oriented country musicians.  U2 release their seventh album Achtung Baby, considered by many of their fans to be their best album. Metallica also release their most commercially successful self-titled album, and the Red Hot Chili Peppers break through to the mainstream with their critically and commercially acclaimed Blood Sugar Sex Magik. R.E.M. release their massive commercial breakthrough album Out of Time. 1991 also brought us the revolutionary Sailing the Seas of Cheese, the first release of a Primus album on a major label.

When it came to music, 1991 was one of the most successful years of the 90's.