This volume offers a historical and factual commentary on Herodotus book 6. The introductory discussions include one on the background to the Ionian revolt and the role of Histiaeus. The commentary aims to assess the reality behind Herodotus' text: the revolt and its aftermath; the various aspects of Spartan affairs in the middle of the book; Datis' invasion of Eretria and Attica; and Miltiades' expedition the following year. Material that cannot conveniently be dealt with in the commentary itself, and a number of related topics that merit consideration, are considered in a series of appendices. These include discussions of Cleomenes' madness in relation to his activities in Arcadia, and the Argive reaction to his victory at Sepeia.