Satyrus (Greek: Σάτυρος) of Callatis was a distinguished peripatetic philosopher and historian, whose biographies (Lives) of famous people are frequently referred to by Diogenes Laërtius and Athenaeus. He came from Callatis Pontica, as we learn from a Herculaneum papyrus. He lived earlier than the reign of Ptolemy VI Philometor (181-146 BC) when his Lives were epitomized by Heraclides Lembus, and he may have lived in the late 3rd century BC. Athenaeus frequently refers to him as a Peripatetic, but his connection to the Peripatetic school is otherwise unknown. His biographies dealt with many eminent people including kings (Dionysius the Younger, Philip), statesmen (Alcibiades), orators (Demosthenes), poets (Aeschylus, Sophocles, Euripides), and philosophers ((Bias of Priene, Chilon of Sparta, Pythagoras, Empedocles, Zeno of Elea, Anaxagoras, Socrates, Diogenes, Anaxarchus, Stilpo). He also wrote on the population of Alexandria, and a work On Characters (Greek: Περὶ χαρακτήρων). Fragments of his biography of the Athenian dramatist Euripides were found at the end of a papyrus scroll discovered at Oxyrhynchus in the early twentieth century. They show that he used not very reliable sources for his biographies. For example he interpreted the verses of the works of Euripides to win material for his vita of this great tragedian. For the same purpose he took carelessly statements from the Greek comedy, especially Aristophanes, who had sharply criticized Euripides. Besides he did not name his other sources. Judged by modern standards he is therefore not a very reliable biographer.