Knowledge of Xerxes is limited by the material available. Persian sources are fragmentary and are unable to give the balance historians need to make an adequate assessment. Most of the written sources are Greek and these accounts have influenced modern historians.
Herodotus was born about 484BC and is the most contemporary of the ancient sources. He also travelled in the Persian empire. He is probably the most balanced writer, presenting Xerxes as generous and compassionate, appreciative of natural beauty, but unstable, intolerant of criticism and weak-willed.
Aeschylus was also a contemporary, who fought at Marathon and possibly at Salamis. He portrays Xerxes in his play The Persians as a weakling to be despised. He wished to demonstrate that everything Greek was superior.
Xenophon, writing in the fourth century BC, sees Xerxes as a tyrant and a womaniser.
Later ancient historians have followed this tradition. Although Pausanius tells that Xerxes’ achievements were glittering and Josephus praises his piety, Aelian calls him ridiculous and Cicero despises him.
Early scholars saw him as debauched and slothful, weak and degenerate; later scholars are more balanced, trying to judge him in the Persian context of his day.
P.Green (The Greco-Persian Wars, Berkeley, 1996) sums up the position: “Our traditional picture of Xerxes is a caricature, put together from hostile, and faintly contemptuous, Greek propaganda. We see him as…a cowardly despot ruled by his women and his eunuchs…cruel in victory, spineless in defeat. Persian sources…reveal a very different man. Tall, regal and handsome he stands in the Persepolis reliefs, and his proclamations have a ringing dignity which echoes down the ages…”
The Western Tradition
The Western tradition holds Xerxes to be effeminate, ostentatious, a weakling, intolerant, given to fits of temper, brutal, and craving luxuries. Later in his career, he is simply seen as a weak ruler controlled by women and court eunuchs.