Hesiod, a poor farmer, was believed to have written in the ninth, sometimes eighth century. Hesiod was the author of several significant poems, the most meaningful being the Iliad, Odyssey, and Theogony. Hesiod was believed to have been the first man in Greece to wonder how everything had happened, the world, the sky, the gods, mankind, and to think out an explanation. The Theogony is an account of the creation of the universe and the generations of gods, and this has been proven to be very useful in increasing our knowledge about Greek mythology.
Aeschylus was the oldest of the three tragic poets, the other two being Sophocles and Euripides. Except for Aeschylus' Persians, written to celebrate the Greeks victory over the Persians, all of his plays contain mythological subjects. Along with Homer, these works provide the main foundation of our knowledge of Greek mythology.
Apuleius, a Latin writer, was believed to have written in the second century AD. The famous love story of Cupid and Psyche is told only by Apuleius, who writing style and patterns have often said to have mimicked Ovid.
Apollonius of Rhodes is said to part of a class of poet's known as the Alexandrian poets. They were called this because when they wrote the center of Greek Literature moved from Greece to Alexandria in Egypt. Apollonius of Rhodes has been given credit for telling the tale of Jason and his search for the Golden Fleece, in the everlasting tale of The Quest of the Golden Fleece.
Theocritus is said to be part of the group classed as the Alexandrian Poet's, along with Apollonius of Rhodes, Bion and Moschus. His writing style maintained a median level between the gravity of the deeply religious writers and the frivolous writers, such as Ovid. He maintained a balance that has given us a different perspective on Greek mythology.