Herodotus (/hɪˈrɒdətəs/; Ancient Greek: Ἡρόδοτος, Hēródotos, Attic Greek pronunciation: [hɛː.ró.do.tos]; c. 484 – c. 425 BC) was an ancient Greek historian who was born in Halicarnassus in the Persian Empire (modern-day Bodrum, Turkey). He is known for having written the book The Histories (Greek: Ἱστορίαι Historíai), a detailed record of his "inquiry" (ἱστορία historía) on the origins of the Greco-Persian Wars. He is widely considered to have been the first writer to have treated historical subjects using a method of systematic investigation—specifically, by collecting his materials and then critically arranging them into an historiographic narrative. On account of this, he is often referred to as "The Father of History," a title first conferred on him by the first-century BC Roman orator Cicero.

Despite Herodotus's historical significance, little is known about his personal life. His Histories primarily deals with the lives of Croesus, Cyrus, Cambyses, Smerdis, Darius, and Xerxes and the battles of Marathon, Thermopylae, Artemisium, Salamis, Plataea, and Mycale; however, his many cultural, ethnographical, geographical, historiographical, and other digressions form a defining and essential part of the Histories and contain a wealth of information. Herodotus has been criticized for the fact that his book includes many obvious legends and fanciful accounts. Many authors, starting with the late fifth-century BC historian Thucydides, have accused him of making up stories for entertainment. However, Herodotus states that he is merely reporting what he has seen and been told, on several occasions saying that he does not himself believe the story that he reports. A sizable portion of the information he provides has since been confirmed by historians and archaeologists.