Songfacts®:

• Do you hear that thunder?
  That's the sound of strength in numbers
  
  Following the release and success of Idles' 2018 album Joy as an Act of Resistance, frontman Joe Talbot got criticized for speaking up for socialism and the rights of minorities. He wrote this defiant post-punk stomper as a response. "I want to sleep at night knowing that my platform is the voice of reason and an egalitarian want for something beautiful," he told Apple Music. "Not the murder of Black people, homophobia at the workplace, racist front lines."
• "Grounds" is a marching tune, spoke-sung by Talbot over a brutal but simple beat and bursts of guitar. Talbot described it as "a song that embodied self-belief, and gave us self-belief - a counter-punch to all the doubt we build up from all the noise we so easily let in."
• Talbot addresses Britain's colonial past.
  
  Sayin' my race and class ain't suitable
  So I raise my pink fist and say black is beautiful
  
  He explained to the BBC he believes those people who want to "make England great again" are ignorant of their country's past. "They don't know what genocide happened to make the empire what it was, and how important immigration is, and the National Health Service is, and socialism was as a construct in building our country, the welfare system, and looking after the poor," he said. "We are now in a class war, and the poor are losing massively. I'm just fed up with England."
• Idles previewed "Grounds" during their late 2019 tour before releasing it as the lead single from Ultra Mono on June 16, 2020. The album further explores themes established in the band's previous two records, such as the class struggle and racist attitudes. "We wanted to make the sound of our own hearts' marching band, armed with a jackhammer and a smile," Talbot explained of this song. "We wanted to make the sound of our engine starting. So we did."
• Idles were recording in Paris when Warren Ellis of The Bad Seeds and Grinderman popped into the studio. He is friends with Ultra Mono co-producer Nick Launay, and Talbot asked the Australian musician to contribute a "Hey!" to the song.
  
  Ellis recalled to Uncut magazine: "Joe turned to me and said, I'd really like to have some backing vocals like Malcolm Young. And seeing as you're Australian, you can do grunts, like on [AC/DC's] 'T.N.T..' The thing I like about Idles that I saw in the studio is that they're very much a group, and there's power and strength in a group. They see the potential in that, and that's an unusual trait these days. It was really great to see their love for being in a band."
• Colin Webster plays the saxophone; it's one of five Ultra Mono tracks he performs on.