1991 was a game changing year mostly known to music-geeks as the “year punk-rock broke” – i.e.- the year Nirvana kicked Michael Jackson out of the number one album chart and saved the world from increasingly awful hair metal bands. In addition to the classic “Nevermind” by Nirvana, “Badmotorfinger” (Soundgarden’s mainstream breakthrough), “Ten” (the debut album by soon to be world-dominating Pearl Jam), and “Gish” (the still underground but great debut by The Smashing Pumpkins) all happened in ’91. Grunge music, primarily from Seattle, completely dominated the U.S. alternative scene.
British music was in its pre-Brit-pop era- dominated by the baggy, post-rave music lead by the excellent Primal Scream and Blur (with their debut album) along with lesser bands like The Farm & The Soup Dragons and the even dancier music of The Pet Shop Boys, Future Sound of London, Orbital, The Orb & Saint Etienne- much of which could be classified as full-on House music. “My Bloody Valentine” released their epic masterpiece “Loveless” which set the bar for the entire shoegaze movement.
Rap music experienced one of the best year’s in its history to date with great pop-rap tracks like “O.P.P.” and “Summertime” placing high on the pop charts and conscious-rap Native tongues groups like A Tribe Called Quest, De La Soul & Black Sheep all releasing brilliant, inventive albums alongside harder-edged rappers Public Enemy, Gang Starr and Ice Cube.
’91 would set off a 4 year period of great music where some extremely left of center music would be able to compete in the mainstream.
Nirvana- Nevermind
Buy 
Buy Nevermind
The Pixies- Trompe Le Monde
Buy Buy Trompe le Monde
De La Soul- De La Soul is Dead
My Bloody Valentine- Loveless
Buy Buy Loveless
Massive Attack- Blue Lines
Buy Buy Blue Lines
Pearl Jam- Ten
Buy Buy Ten
Soundgarden- Badmotorfinger
Buy Buy Badmotorfinger
Primal Scream- Screamadelica
Buy Buy Screamadelica
Public Enemy- Apocalypse ’91: The Enemy Strikes Black
Buy Buy Apocalypse 91…The Enemy Strikes Black
Smashing Pumpkins- Gish
Buy Buy Gish
U2- Achtung Baby
Buy Buy Achtung Baby
Uncle Tupelo- Still Feel Gone
Buy Buy Still Feel Gone
Black Sheep- A Wolf in Sheep’s Clothing
Buy Buy A Wolf in Sheep’s Clothing
Gang Starr- Step In the Arena
Buy Buy Step in the Arena
Teenage Fanclub- Bandwagonesque
Buy Buy Bandwagonesque
Ice Cube- Death Certificate
Buy Buy Death Certificate
A Tribe Called Quest-The Low End Theory
Buy Buy The Low End Theory
Fugazi- Steady Diet of Nothing
Buy Buy Steady Diet of Nothing
Talk Talk- Laughing Stock
Buy Buy Laughing Stock
Red Hot Chili Peppers- Blood Sugar Sex Magik
Buy Buy Blood Sugar Sex Magik
Album via Amazon 
album via Amazon 
7″ Single via Amazon 
album via Amazon