Aśvaghoṣa is considered one of the greatest Indian poets before the time of which Sanskrit writer and dramatist?
Aśvaghoṣa:  He is believed to have been the first Sanskrit dramatist, and is considered the greatest Indian poet prior to Kālidāsa. Kālidāsa: Kālidāsa was a Classical Sanskrit writer, widely regarded as the greatest poet and dramatist in the Sanskrit language.
Kālidāsa