burnt the city, leaving an archaeologically attested destruction layer, known as the Perserschutt. The Persians thus gained control of all of mainland Greece to the north of the Isthmus of Corinth. Battles of Salamis and Plataea Xerxes was induced, by the message of Themistocles (against the advice of Artemisia of Halicarnassus), to attack the Greek fleet under unfavourable conditions, rather than sending a part of his ships to the Peloponnesus and awaiting the dissolution of the Greek armies. The Battle of Salamis (September, 480 BC) was won by the Greek fleet, after which Xerxes set up a winter camp in Thessaly. According to Herodotus, fearing that the Greeks might attack the bridges across the Hellespont and trap his army in Europe, Xerxes decided to retreat back to Asia, taking the greater part of the army with him. Another cause of the retreat might have been that the continued unrest in Babylon, a key province of the empire, required the king's personal attention. He left behind a contingent in Greece to finish the campaign under Mardonius, who according to Herodotus had suggested the retreat in the first place. This force was defeated the following year at Plataea by the combined forces of the Greek city states, ending the Persian offensive on Greece for good. Construction projects After the military blunders in Greece, Xerxes returned to Persia and oversaw the completion of the many construction projects left unfinished by his father at Susa and Persepolis. He oversaw the building of the Gate of All Nations and the Hall of a Hundred Columns at Persepolis, which are the largest and most imposing structures of the palace. He oversaw the completion of the Apadana, the Tachara (Palace of Darius) and the Treasury, all started by Darius, as well as having his own palace built which was twice the size of his father's. His taste in architecture was similar to that of Darius, though on an even more gigantic scale. He had colorful enameled brick laid on the exterior face of the Apadana. He also maintained the Royal Road built by his father and completed the Susa Gate and built a palace in Susa. Death and succession In August 465 BC, Artabanus, the commander of the royal bodyguard and the most powerful official in the Persian court, assassinated Xerxes with the help of a eunuch, Aspamitres. Although Artabanus bore the same name as the famed