Reginaldo degli Scrovegni was a Paduan nobleman of the Guelph faction who lived in the 13th century just before the time of Giotto and Dante.
He is best known for being cited as a usurer by Dante in the Divine Comedy, and to be the father of Enrico degli Scrovegni, who commissioned the famous Arena Chapel painted by Giotto.
In Dante Alighieri’s Divine Comedy poem Inferno, Dante says that he saw Reginaldo in the inner ring of the Seventh Circle of Hell, where the violent are eternally punished.
The inner ring of the Seventh Circle is a burning hot desert with a continual rain of fire.
This, and a bit of research into Dante's time-period, make it possible to identify who the suffering sinners are meant to be.