This slice of acoustic melancholy was one of the first songs frontman Chris Cornell penned for King Animal. He told Artist Direct: "It was actually in a period of rehearsals before we were even sure we were going to write a new album. I was doing rehearsals for Songbook. I was sitting with an acoustic guitar and playing. Every once in a while, I'd be spacing out and playing something. It's cool I'd record it on my laptop with the mic there. Suddenly, and I don't really know why, I started coming up with ideas I thought would make great Soundgarden songs. That hadn't happened in a long time. I hadn't really thought like that. That was the only one of about four or five that I turned into a Soundgarden song. It felt like something that would fit with us because you can't really nail it down in a sense. Stylistically, it's its own thing. It's also a new thing to me. I don't know that I've really heard a song like that. I can hear influences in it. There's something about the bass, the vocal delivery, and the melody that reminds me a little bit of The Beatles and Paul McCartney. There are elements that just sound like Soundgarden to me though."

The lyrical concept came from a conversation Cornell had had many times with friends. He explained: "You'll see a person in a situation and say, 'If somehow I manage to wander into that situation without understanding that I'm doing it, make sure to let me know' [Laughs]. "If 'Fell On Black Days' was about waking up and realizing you're in a dark period of your life," he continued 'Black Saturday' is asking somebody to warn you if you don't realize you're heading in a direction where you might wake up one day and end up in a bad part of your life."