A lot of people have one album that changes their lives, something that in some way alters everything after the first moment the hear it. 1999's Agaetis Byrjun is that album for a lot of people. Agaetis Byrjun (a good beginning), is actually Sigur Ros' second beginning. Three years previously they released their debut album, Von. After that the trio became a quartet and they evolved into something astounding. As suggested by a lyric from Agaetis Byrjun's title track, Sigur Ros had bigger ambitions after releasing Von.

Agaetis Byrjun gradually grew into a huge commercial success in Iceland, remaining in the top of the charts for over 2 years. Dave and Alex from Fat Cat Records had had their eye on Sigur Ros since 1998 and quickly signed the band to their label following Agaetis Byrjun's release. The first indication of the critical acclaim the album would receive abroad came with the release of the Svefn-g-englar EP in September 1999. Ecstatic reviews began emerging and gushes like "the last great band of the twentieth century" and "like god weeping tears of gold in heaven" were not uncommon.

Agaetis Byrjun became available to the rest of the world in 2000 when Fat Cat released the album in the UK, and in 2001 when PIAS Recordings released the album in North America. Agaetis Byrjun was an album that came literally out of nowhere and seemed to tug at the heartstrings of those who least expected it. No one thought an album by an unknown band of four shy Icelandic men in their early-20s, singing in Icelandic, would become the worldwide music phenomenon it became. The record label projected the album to sell 1500 copies - it has to date sold several million copies.