Since Kanye first appeared on the music scene, he's gone through multiple transformations — brash young Jay Z-endorsed rapper, enfant terrible of the music world, aspiring fashion visionary, frequent Twitter prophet, Kardashian consort, and artist battling his demons. Throughout the reninventions, however, one thing has remained constant and that's Kanye's indomitable belief in himself.
Call it ego, hubris, or narcissism, but Kanye's supreme assurance in himself is what has made him a cultural phenomenon for close to two decades, something he's well aware of — this is the man, after all, who once declared himself "the greatest artist of all time" and wryly wrote the lyrics "I love you like Kanye loves Kanye." This braggadocio has also given birth to some of the most memorable instances in pop culture: when he rushed the MTV Video Music Awards stage during a Taylor Swift acceptance speech, when he unforgettably made his point about former President George W. Bush's handling of Hurricane Katrina on live television, and more recently, when his fashion shows had no shortage of drama.
In honor of his 40th birthday, TIME looked back at the most noteworthy moments of Kanye being unapologetically Kanye.