Xenophon of Athens (circa 430 354 B.C.) was a Greek poet, historian, soldier and philosopher, living at a time of momentous events in Ancient Greek history, writing about the philosophy of Socrates, the Peloponnesian War between Athens and Sparta, and the Persian expedition that formed the basis of his most famous work, Anabasis. In addition to his own works, he influenced the account of the Peloponnesian War written by the famous Greek historian Thucydides. Although he was recognized as a great writer and poet in his lifetime, Xenophons involvement with Spartan politics and fighting led to his exile from Athens, and his association with Socrates probably did not help. His short treatise on Spartas government is considered one of the first examples of political philosophy. Anabasis is Xenophons most famous work and is a classic war adventure account. Xenophon accompanied a large army of Greek mercenaries that invaded Persia at the behest of Cyrus the Younger, who sought the Persian throne. Things go south in a hurry, and Cyrus is killed, leaving much of the book to detail the survivors escape from enemy territory. Along the way, Xenophon describes what he saw in Persia, also making it an important historical assessment of the Persians.