Xenophon, an Athenian volunteer later chosen as a general, wrote the Anabasis as the story of Greek mercenaries walking home from the heart of Persia, the lands we now call Iraq and Iran. This is Book 4. By Book 3 the Ten Thousand had lost their employer at Cunaxa and their commanders in a Persian trap; they elected new leaders, including Xenophon, and pushed through the Carduchian mountains of eastern Turkey as a moving camp with little food.

They now climb into Armenia in the snow. Men sit down in the white and will not rise. They take a fort by driving oxen up as a living shield. Tiribazus, a Persian governor, almost traps them with a treaty. They cross the Centrites river under arrows. From a mountain the men in front begin to shout. Xenophon, at the rear, thinks it is an ambush. It is the Black Sea, the first Greek water in months. They pile stones for Zeus. Trapezus, a Greek colony at today’s Trabzon, is still days off, but the water is under them. After the shouting they weep like boys. The sea is a road if they can reach a port.