A great history of the Greco-Persian Wars from the Spartan perspective. Also an impressive study in the analysis of source material; Rahe is very transparent about how he uses primary sources, why he favors one over another with respect to X or Y event, and talks at length about how he uses things like geography, weather, archaeological findings, and so forth to make sense of what they report. Some might find this a little discursive, but if you're interested in how the history sausage gets made, it's an invaluable read.
Thoughts from my read:
* You can't understand Sparta without understanding that everything they did (or didn't do) had to take the helots into account. The Spartan way of life depended entirely on the slave labor provided by the helots, but the Spartans were massively outnumbered by their slaves. The Spartans knew they were riding the tiger and their society reflected it. Other books that I've read about Sparta discuss this, but Rahe makes this clear as day and drives the point home repeatedly. Any foreign policy decision made by the state had to consider the helots.
* Ghela. In the 1930s, archaeologists found a brick inscribed in Old Persian and attributed to Darius. That's not particularly interesting until you consider that Ghela is in northwestern Romania. The high water mark of the Persian empire? "...Herodotus reports that, in his time, there lived beyond the Danube a mysterious people called the Sigynnae, who dressed in the Median manner and claimed to be colonists drawn from among the Medes." Reminds me of colonies of Alexander's Greeks after the collapse of his empire and the slow disintegration of the successor states. How long did the Sigynnae manage to cling to their Median-ness so far from home?
* Thermopylae and Sparta. The stand at the Hot Gates changed things for the Spartans. "Of the three hundred Spartans dispatched to Thermopylae, there appear to have been three who were in no position to contribute in any substantial way to the struggle against the Mede. Eurytus and Aristodemos were purportedly laid up in Alpenus -- both with diseases of the eye. In the crisis, if Herodotus has the story right, the first of the two armed himself and asked the helot assigned to him to lead him into the fighting; and there, as anticipated, he lost his life. The latter was too feeble to follow his example, and he survived the final battle and eventually made his way back to Lacadaemon. There, however, he was shunned: no one would speak to him or even share fire with him, and behind his back they referred to him as a "trembler." His was, he discovered, a life not worth living, and at the battle of Platea he put an end to that life by charging the Persians in such a fashion as to guarantee that he would be impaled upon their spears. There was also a third Spartan name Pantites, who had been sent away to Thessaly as a messenger and, in consequence, missed the final battle. When he returned to Sparta, he was treated with such contempt that he hanged himself." Spartiates were now on notice that even reasonable excuses for failing to do their part were no excuses at all.
* Beheading as motivation, just not the kind of motivation desired. In the aftermath of the Persian loss at the naval battle at Salamis, "...after ...the Great King had ordered the beheading of some of the Phoenician trierarchs, he had threatened to inflict on the rest the punishment he thought they deserved, and at least some of the ships from Sidon and Tyre had fled ... they... hoisted sails and headed home." Whoops.
* Logistics. Persia didn't do half-measures, and their armies and navies were enormous. We can quibble about numbers, but in a pre-industrial world they were huge, and required tremendous resources to feed, water, and transport. They couldn't tarry for very long in any one spot, and put a great deal of pressure on vassals who had the pleasure of hosting the royal procession. Weather patterns also had a big role to play; sailing in the ancient world was a dicey and seasonal business, and the Persian army in Greece depended at least in part on replenishment by sea.
The flip side of this? In addition to being difficult to provision, we see that the Persian forces were generally too large for their own good. The Greeks time and time again were able to bring them to battle in places that either limited the usefulness of the numbers the Persians had at their disposal, or turned their numbers into a problem.
* NATO much? Discussing Sparta's web of alliances that managed to see them through the wars with Persia: "...keep the Messenians down, the Arcadians close, and the Argives out..."
* Scale. The Persian empire included some 40% of humanity. That's a bonkers number. The idea that the Greek statelets were able to set aside their constant bickering and see off a concerted effort on the part of 4 in 10 humans to absorb them into their polity is remarkable, and was a close run thing at a number of points.
* After the Battle of Platea, Pausanias was taken aback by the splendor of the enemy's quarters. He had the Persian servants make him a meal, and was dumbstruck by the spread. He then asked his own servants to produce a meal, which was comparatively humble. Bringing the Greek commanders in to the tent, he said: "I have assembled you for this purpose - to show you the mindlessness of the Persian leader Mardonius, who, having a mode of living like this, came against us to deprive us of the dreary mode of living that we posess."