What happened in 315 AD?

Who is the oldest child of Zeus? Why were the Aztecs god so important to their civilization? Who sprang from the forehead of Zeus? Why was it very difficult to study prehistoric history? What was Hades known associates? Height of Greek City-States? Where did goddess Athena lived? How many years passed between Rome's early days as a little settlement and its invasion in the 5th century? What is the purpose of a false burial chamber in a pyramid? How did perseus succeed in his serach for medusa's head? How do Odysseus and his men sneak out of the cyclops ' cave? Who did king Menes marry? What does paleolithic mean? What is the origin of the mythological creature known as the griffin or gryphon? Why were the Romanov unpopular? How are mount Olympus and underworld similar and different? How did virgil die? How were meroe and napata alike? How did King Darius improve trade in the Persian Empire? How do myths originate?