For centuries, education in the West was based around an in-depth study of the Greek and Latin classics. In recent decades, however, these classic works have fallen off of the curriculum in many schools. Far too many students are able to graduate from high school without ever reading a play by Sophocles or Aeschylus, or without encountering Plato, Cicero, Horace or any of the other literary giants of the Greek and Roman world. However, without having at least a passing familiarity with these writers, it can be difficult to fully understand much of the literature that comes after their time.
Much of the Western canon involves a reaction or response to these earlier writers. To fully comprehend Shakespeare, for example, requires at least some awareness of the body of Greek and Latin literature. Even in recent times, many well-educated writers have peppered their works with references to classic literature. If you do not know to what they are referring, these references will simply go over your head. You may still be able to enjoy the works of these writers, but you will not fully understand what they are trying to communicate.
Fortunately, you do not have to be fluent in Ancient Greek or Latin to still read and enjoy these classic works, though of course such fluency does help. Many fine translators over the centuries have turned their hands to producing readable translations of the great writers of Ancient Greece and the Roman Empire. New translations are always being published, and while these may vary widely in quality, they are nevertheless quite valuable to the enterprising reader. By furthering your knowledge of the classics of ancient literature, you can enrich yourself and your enjoyment of the rest of the literary canon. Soon you will be reading more deeply than ever before.