A. R. (Andrew Robert) Burn.
The Persian Wars: The Greeks and the Defence of the West, c. 546 - 478 B.C.
London: The Folio Society, 2002.

Previously published as:
Persia and the Greeks: The Defence of the West, c. 546 - 478 B.C., Second Edition. London: Gerald Duckworth and Co., Ltd., 1984.
American Edition: Stanford University Press, 1984 (Amazon).

This book covers mostly the same period and events in Greek history as Herodotus (less Egypt and Scythia); thus I found it an excellent sequel to reading Herodotus. In many ways the book is a commentary on and updating of Herodotus, using all the resources of history and archeology accumulated since the time of Herodotus.