For years, experts said a Roman emperor wasn't real. Scientists say a coin could prove otherwise.

An ancient emperor thought to be made up could be real after all, according to researchers who've analyzed an ancient coin bearing his face.

There are four coins on display at the University of Glasgow: one bears the visage of the Emperor Gordian III, two of Emperor Philip and one features Sponsian, said Professor Paul Pearson from the University College London.

The Sponsian coin was found over 300 years ago in 1713 in Transylvania, or present-day Romania. Sponsian has barely a footprint in history and was deemed fictional by historians long ago, Pearson said.

For years, experts said a Roman emperor wasn't real. Scientists say a coin could prove otherwise.