Short answers, pulled from the story.
The play The Frogs by Aristophanes was performed in the winter of 405 BC during the Lenaia festival. This performance took place while Athens faced blockade and imminent defeat in the Peloponnesian War.
Aeschylus won the contest against Euripides because his verses were heavier on a scale used to judge their poetry. Dionysus chose Aeschylus as the poet who could save Athens, though he named Sophocles as his successor before leaving Hades.
The chorus urged Athenians to reject foreign-born leaders like Kleophon and instead support men raised in noble families. They also called for the return of exiled oligarchs who had been cast out during the democracy reinstatement of 410 BC.
Stephen Sondheim adapted The Frogs into a musical that premiered in an Olympic-size swimming pool at Yale University in 1974. Meryl Streep and Sigourney Weaver starred among Yale students in this production which later influenced Nathan Lane's Broadway revision in 2004.