Question

Who or what did Roman theatre celebrate?

Answer 1

But there some very distinct differences. Greek Theaters were carved out of a hillside while Roman theaters were built up from solid ground using either cement or stone. Also the orchestra is larger because the structures were used for other events which required more space.

Andd

The scaenae frons was a high back wall of the stage floor, supported by columns. ... The Roman theatre also had a podium, which sometimes supported the columns of the scaenae frons. The theatre itself was divided into the stage (orchestra) and the seating section (cavea).

and

For example, one of the most famous plays of the Roman Empire was Phaedra, a tragedy written by the great playwright Seneca. It was a Roman retelling of the Greek tragedy of Hippolytus.