Greek literature refers to writings composed in areas of Greek influence, throughout the whole period in which the Greek-speaking people have existed. Ancient Greek literature refers to literature written in Ancient Greek from the oldest surviving written works in the Greek language until approximately the fifth century AD and the rise of the Byzantine Empire. At the beginning of Greek literature are works of Homer, the Iliad and the Odyssey. In the classical period many of the genres of western literature became more prominent. The two major lyrical poets were Sappho and Pindar. The Classical era also saw the dawn of drama. Two of the most influential historians were Herodotus and Thucydides. In the 4th century BC, three philosophers are notable: Socrates, Plato, and Aristotle. Later Greek poetry flourished primarily in the 3rd century BC. During the Roman era, the physician Galen, in the history of ancient science, is the most significant person in medicine after Hippocrates.