"You can pin any label to John Evans and it’s true. He was an influential cartographer, a great British nutter, a pioneering explorer, a Welsh revolutionary, a class warrior and the last Spanish conquistador, dying as a Spanish citizen, Don Juan Evans, in New Orleans.”

Super Furry Animals frontman Gruff Rhys knew the story of his 18th-century relative Evans as a family legend.

But when he was on tour in the US, Rhys decided to trace the route of the first man to map the Missouri River as he travelled across the wilderness in the 1790s to find the fabled Madogwys, the Welsh-speaking Native American tribe.

“He’s like a historical footnote in the US,” says Rhys. “He gets a few sentences about him in a couple of books. Lewis and Clark used his maps in the first year of their exploration to find the Pacific, although he was long dead by then.

“He walked for four solid years, from Baltimore to Pittsburgh down the Ohio River, and the entire distance of the Mississippi and Missouri Rivers for more than 2,000 miles up to the Canadian border.

“He lived with a series of river tribes along the Missouri and would have experienced both the buffalo dance and the Okipa ceremony, where members of the Mandan tribe would hang themselves from hooks and poles. He saw the US before a lot of it was colonised. He was sleeping rough in minus-20 degree snowdrifts, and walking with no map.”

Eventually Evans’s quest ended in disappointment when he realised the Mandans had no Welsh lineage. He died in 1799, before his 30th birthday, a broken alcoholic in New Orleans, his health damaged irreparably by his explorations.

Rhys used his US tour to tell audiences Evans’ story, writing songs to accompany the tale. He brought in documentary maker Dylan Goch to film the shows, having worked with the director on the film Separado! which explored the Patagonian side of Rhys’s family.

Rhys’s new album American Interior uses Evans’s story as a jumping off point and is now accompanied by a film, a book and even an app.

“There was no contemporary book on Evans so I researched all this stuff to make a companion book to go with everything,” says Rhys.

“With the app it’s a project that has gone totally out of hand. We started with a collection of songs and a slide show, and in Brighton we are breaking it back down into that.”

To tell Evans’s full story Rhys has created his own avatar version of the US pioneer who accompanies him on stage.

“I hope I’m not trivialising his character by turning him into a Muppet,” laughs Rhys. “It’s helpful having an avatar as a visual aid to help explain and make people aware that he was real.”

Evans’s story began in his native Snowdonia. Born to a Methodist preacher, he moved to London and fell in with a group of radical Welshmen.

Inspired by the legend of Madoc – who was meant to have discovered America in 1170, more than 300 years before Columbus – Evans mounted an expedition to find the mythical lost Welsh-speaking tribe made up of his descendants, who supposedly lived in the largely unmapped west.

“Nobody would bankroll him,” says Rhys. “In the end he borrowed enough money to cross the Atlantic. In 1792 he got a job in a Baltimore surveyor’s office for six months and saved one dollar and 75 cents, before he went walking into the wilderness.”

Dangerous territory

He walked out into dangerous territory. The British had been arming the Ohio tribes to battle the emergent US Army, adding to the very real natural dangers of a wilderness inhabited by snakes, bears and alligators.

“Within six months of starting his journey, he had contracted malaria, run out of money and had no clothing,” says Rhys.

When making the album, Rhys didn’t want to simply tell Evans’s story – electing that each song should be able to stand on its own.

Aside from the song 100 Unread Messages, which goes deep into Evans’s history, the rest of the album follows more of an emotional journey, without getting too specific.

“It’s the role of the film and the book to tell the specific narrative,”

he says. “I have taken more liberties with the songs. There is a narrative arc, but hopefully it’s not too stifling.”

Rhys was keen to avoid falling into an imitation of American country rock.

“I didn’t want it to be an embarrass-ing situation of a European person try-ing to make a US roots record,” he says.

The solution came from the fact he had just finished making Praxis Makes Perfect, the second album by Neon Neon, his side project with producer Boom Bip.

“We still had some of the synthesisers we had used on that record. There are a lot of country rock and US musical references, but I wasn’t trying to make a purist country record – there’s enough of a balance there with the synths.”

The tale of John Evans shows there is a wanderlust in the Rhys blood, which was also explored in the 2010 documentary Separado! It saw the singer explore Patagonia to meet members of his family whose ancestors had emigrated there from Wales in the Victorian era.

“My family is very normal for the most part,” says Rhys. “They all work for public services and work hard to help people. I’m a bit of an odd one out with a very frivolous job. Every family has really strange stories, I’m just verifying whether they are true or not.

“Evans reminds me of an early rock and roll pioneer – like a Hendrix character whose explorations led him to an early grave.”