He was the scientist who made one of the planet’s most significant discoveries: the existence of dinosaurs. Yet Gideon Mantell’s place in history has for two centuries been overshadowed by a rival who stole his thunder. Now, Mantell is finally set to get his moment in the spotlight, in a new play that charts the little-known story of a man that science left behind.

Mantell’s discovery, in 1822, of an enormous fossil during a dig in a Sussex quarry would later be classified as the first known Iguanodon tooth. Mantell, the son of a cobbler, had a eureka moment, realising the items he was unearthing belonged to a previously unknown creature.

“Scientists had been baffled by the discovery of dinosaur bones for decades; people thought they belonged to giant people. The critical thing that Mantell did was to recognise that these bones belonged to giant animals,” said James Yeatman, director of the new play, Dinomania.

Mantell’s realisation was a major breakthrough. But science itself was in the throes of a great change that would eventually lead to the publication of Charles Darwin’s On the Origin of Species in 1859. A battle was being waged between the religious and scientific theories of evolution.

On the religious side stood a group of eminent scientists – among them Richard Owen. Owen was a figure of high society, a friend of the royal family, and had helped establish the Natural History Museum in London. But he had never been an ardent collector of fossils. His obsession, said Lauren Mooney, the play’s co-writer, was “trying to prove that dinosaurs were part of God’s creation – God’s monsters – rather than our ancestors … And he was very, very good at it.”

Richard Owen was a highly influential figure in scientific circles and helped to found the Natural History Museum. Photograph: Science & Society Picture Library/SSPL via Getty Images

Owen was ruffled by Mantell’s discovery, Mooney said, and set about discrediting his research in support of the aristocratic and conservative wings of science. He used his influence to re-classify the fossils as “God-created beasts”, but crucially, at the same time, coined the name “dinosaur” to describe them, Mooney said. “People had been happy to believe in weird mythical creatures like unicorns, so dinosaurs came along at the right time. They replaced those things in the collective imagination – but it was Owen, not Mantell, who took most of the credit.”

The play, which is on at the New Diorama Theatre in London from 19 February to 23 March, captures Owen’s triumph while Mantell self-destructs. “Mantell wanted to punch his way into the scientific elite but it never happens for him, and he impoverishes his whole family,” said Yeatman.

In the play, Mantell’s long-suffering wife, Mary, leaves him and takes their children with her. “He becomes a broken man,” Yeatman said.

Towards the end of the play, Mantell – crippled after a horse accident – is visited by Owen, who, so the story goes, takes the Iguanodon tooth for himself.

Some of the scenes in the play might not stand up to forensic historical scrutiny, admitted Mooney, but it is intended as a creative adaptation and has a wider theme relevant to the modern world.

“It’s about extinction and climate change, and the wider issue of who really gets to drive progress,” said Mooney.

“These questions about access to science are still alive today. How many women, how many people of colour, how many outside the elite get to progress through science? Yet that obviously drives the direction of research and what is deemed to be important.”

David Unwin, a palaeontologist at the University of Leicester, agrees that today’s research is still often about “ownership and who controls the access”.

China’s fossil record is the modern-day example of this, he says. “It’s the new gold rush for palaeontologists, but who gets to actually see the fossils – it all comes down to power and control, much as it did in Owen and Mantell’s day.”