For Kieran Dodds, photographing people with red hair has become something of an obsession over the past decade. The 45-year-old, from Edinburgh, who is himself a "proud ginger", began taking pictures in his homeland in 2013 as part of a series examining Scottish identity. His interest in the subject soon took him to other ginger hotspots such the Russian city of Perm and Jamaica's Treasure Beach. His 2020 book Gingers spanned the world but after its release he noticed there was a "huge gap". "I realised I didn't have any American citizens," Kieran told the BBC.

Nicholas Modaressi says his dad, who grew up in Iran, refuses to get his genetics tested. "I'm Persian," he tells his son Nic, who grew up in Maryland "I was like 'oh wow, of course, the whole world is in the States'," Kieran says. "It's a microcosm." He says a message from a Native American man who had red hair instantly aroused his curiosity. "I found it very interesting and it made me think, 'where on earth did it come from?'"