The Histories begins by announcing itself as the showing forth of the inquiry of Herodotus of Halicarnassos, undertaken so that the deeds of men shall not be forgotten and so that the causes of the war between Greeks and Persians may be remembered. From the first sentence the book frames itself as research into cause, not merely a chronicle of events.
Herodotus opens with competing legends about who first wronged whom, citing what Persian and Phoenician learned men say about a chain of abductions, before setting myth aside and turning to a man he says he knows did real injury to the Greeks: Croesus, the rich king of Lydia. The story of Croesus introduces the book's deepest theme. Solon the Athenian, shown the king's treasures, refuses to call him the happiest of men, warning that the Deity is envious and that fortune can overturn anyone before the end of life.
Croesus ignores the warning, misreads an oracle that promised he would destroy a great empire, attacks Persia, and destroys his own empire instead. Standing bound upon the pyre, he remembers Solon's words. From here the narrative follows the growth of Persia under Cyrus, Cambyses, and Dareios, tracing how a single power came to rule from the Aegean to the edge of India.
Around this spine Herodotus builds enormous digressions. He devotes whole books to the geography, monuments, religion, and customs of Egypt, to the Scythians of the north, and to the histories of Lydia, Babylon, and the Greek cities. These ethnographic accounts are treated as essential to the inquiry: to understand the conflict, one must understand the many peoples drawn into it and how widely their ways differ.
The later books, continued in the second volume, carry the story to the great Persian invasions of Greece: the stand of Leonidas and his small force at Thermopylae, where the dead are remembered by an inscription saying they lie there faithfully keeping their laws, and the sea battle at Salamis where the vast invading fleet was broken. Throughout, the same conviction recurs: human prosperity is precarious, the proud are humbled, and the end of every matter must be examined before it can be judged.