Explanation: Well into the Imperial era, even the Romans considered Greek writers to be the undisputed masters of tragedy and drama. This meme pokes a bit of fun at the Roman writer Virgil's Aeneid, which is a (made almost from whole cloth) founding legend of Rome, and is appropriately filled with all the right Roman virtues and parallels to future Roman events. As the meme notes, it is highly regarded for its skillful construction and imagery.
Homer is a Greek writer, the writer of the famous Iliad and Odyssey, filled with larger-than-life heroes with detailed intrigue, personal, and interpersonal struggles, against both each other and their enemies. Sorry, Virgil, I think Homer has you beat!
Interestingly enough, Roman comedy and satire is generally regarded more highly than Greek comedy and satire. Something about showing the warts in society, one supposes!