In 2001, System of a Down reached new heights with their Toxicity album, but rather than rush into a follow-up, the band opted to release an odds and ends collection called Steal This Album in 2002. By the time 2004 rolled around, the band had plenty to say and a lot of music set to come out of them.
"The whole world's gone crazy over the past couple of years, so that's brought out a lot of emotions and affected our songwriting," stated guitarist Daron Malakian to Rolling Stone. "We just want to make a great rock record, a record that will be heavy, but heavy in emotion, not just riffs." He elaborated to Launch that war back home factored into the process, adding, "The last two or three months or whenever that happened was probably the toughest time of my whole life. Because it was like not knowing what's going on until we got a phone call. And we get a phone call and they're OK and we can breathe a little bit. For one month I didn't know if a bomb dropped on my grandmother's house or, you know what I mean? I didn't know. It could have. It brought out a lot of good material — not necessarily political music, just emotional music, you know?"
And while System had a certain style and sound that put them on top, the band was open to not so obvious influences such as Kraftwerk, the Beach Boys and the Zombies. "We mixed a lot of styles together without making them seem like they don't belong together," said the guitarist. "We're going to give everybody the System of a Down roller coaster, but don't expect it to sound like it has before."
The band started writing and rehearsing in North Hollywood in January of 2004, then decamped to the famous Houdini Mansion in the Laurel Canyon hills of Hollywood where producer Rick Rubin had recorded Red Hot Chili Peppers' Blood Sugar Sex Magik and would later work with acts like Audioslave, Slipknot, Linkin Park and more.
As the process continued, the band realized they had more than enough material to go beyond the traditional album format and while initially expected to have a new album by the end of 2004, they pushed the timeline into 2005 with not one, but two discs. Singer Serj Tankian revealed to Billboard, "There has been a great deal of upheaval for all of us over the past year or so and that has brought fourth a lot of emotional material. There's a good amount of social commentary in the new songs, as well as songs where we deal with love, with reminiscing, relationships, politics and funny experiences."
Still, the idea of a double album was a little bit daunting for the band. Malakian stated, "You don't have a bunch of kids dropping acid like they used to. You can't just release double albums and expect people to sit there and devote their time to it. Our songs are tough to digest and I would feel really uncomfortable handing someone a CD with 25 songs staring them in the face." Rubin agreed, telling Billboard, "Everything in today's culture is short term and disposable. We're living in a time when people don't seem to even listen to one full album, so we felt the only way for it to get properly heard was to spoon feed it."
As such, the band issued the Mezmerize portion of their double disc on May 17, 2005 with the Hypnotize portion arriving just over six months later on Nov. 22, 2005.
"Doing a two-album set never entered into our thought process," Malakian admitted to Billboard. "But when we looked at all the songs we had and arbitrarily tried to choose 'the best' 14 for one album, we realized we had two album's worth of really great songs, and that they all connected with each other."
System of a Down, "Hypnotize"