Once, when Robert Plant was travelling the US on tour, he briefly stopped by a bookstore in Colorado. In the years leading up to his visit, he’d been between places whilst on the road but was drawn to the south. He described it as having a culture of European immigrants and wound up on a quest to see what had gone on in a time before the Europeans moved through.

The period before the rounding up of the great Comanche empire was of huge interest to him, given the empire, built by the Comanche tribe of Native Americans, fell victim to European colonialism in 1875. Plant was fascinated. “I started trying to track down what happened, the change of power, the hierarchies, the push through to the west coast by the European travellers and the whole frontier spirit,” he told BBC Radio 5. “I was constantly amazed by what I was reading about the tenacity and the wisdom and the guile of the original fathers of the new world.

He was amazed at how Nerburn charted both the guilt and the adventure in tandem: “The whole idea of being so uncomfortable with getting too close to something that’s so profound, that you just feel like some sort of spaceman trying to even comprehend what these guys carry with them, the way they touch the earth.”

Once he’d finished the book, he decided he had to meet Nerburn, if not to ask him more about why silence was so important to Native Americans. “It’s [been] a treasure,” Plant said. “I don’t really do it great service. Since Kent and I have met, I spend quite a lot of the time babbling and enthusing, and being the same ‘RP’ that I’ve been for many years. But I do find my silence. I live close to the Welsh borders, and I know the special places to go, to be, to actually recharge.”

Famous for his shockingly high shrieks with Led Zeppelin, silence is an alien concept for Plant. He described the sheer volume of his performances at times becoming too much, “almost like it was every second had to be filled with some musical comment”. He mentioned that in the early days of his career, insecurity and nervousness led, “like most Western communications,” to too much noise.

But, with the book’s spiritual take on the importance of silence, he learned to find it. “It’s got more and more fluent, my time in silence since,” he said. “I’m very pleased with that.”