Updated: Sep 8
His mother was Atossa, daughter of Cyrus the Great, and husband of Darius the Great. Xerxes, therefore, did not have to prove himself to be the king. He married the princess Amestris, daughter of Otanes, who would become the mother of his sons Darius, Hystaspes, Artaxerxes I, Achaemenes, and daughters Amytis and Rhodyne.
Upon assuming the throne in 486 B.C., Xerxes crushed revolts in Egypt and Babylon that had broken out the year before, and appointed his brother, Achaemenes, as satrap over Egypt. He outraged the Babylonians by violently confiscating and melting down the golden statue of Marduk, the hands of which the rightful king of Babylon had to clasp each new year's day. This sacrilege led the Babylonians to rebel in 484 B.C., and again in 482 B.C.
Xerxes' commander-in-chief of the army Mardonius, who was also his cousin and brother-in-law, pressured him to renew the campaign against the Greeks. Mardonius' motives were personal as he hoped to rule that conquered nation as satrap following a Persian victory. Xerxes' uncle and advisor, Artabanus, however, tried to persuade him to abandon the expedition, but Mardonius' arguments prevailed.
From 483 B.C., Xerxes prepared for his expedition. He had a canal dug across the Isthmus of Actium near Mt Athos, the remains of which are still present today. He also had provisions stored in the stations on the road through Thrace, and two pontoon bridges constructed across the Hellespont. According to Herodotus, Xerxes' first attempt to bridge the Hellespont failed when a storm destroyed the flax and papyrus cables of the bridges. In retaliation, Xerxes ordered the Hellespont, the water itself, whipped three hundred times, and had a pair of shackles thrown into the water. His second attempt was a success.
Once the preparations were complete, the invasion force set out, in the Spring of 480 B.C., from Sardis with a force realistically of about 60,000 combatants, possibly 100,000 – 150,000 including the supply train and support staff. The Greeks, meanwhile, had mobilized their forces under the direction of Athens. An advance force of about 7,000 Greeks intercepted the Persians at Thermopylae and attempted to block their path. The vastly outnumbered Greeks held off the Persians for seven days (including three of battle) before the rear guard was annihilated in one of history's most famous last stands. The Spartan