premature end to the campaign. However, in 490 BC, following up the successes of the previous campaign, Darius decided to send a maritime expedition led by Artaphernes, (son of the satrap to whom Hippias had fled) and Datis, a Median admiral. Mardonius had been injured in the prior campaign and had fallen out of favor. The expedition was intended to bring the Cyclades into the Persian empire, to punish Naxos (which had resisted a Persian assault in 499 BC) and then to head to Greece to force Eretria and Athens to submit to Darius or be destroyed. After island hopping across the Aegean, including successfully attacking Naxos, the Persian task force arrived off Euboea in mid summer, ready to fulfil their second major objective - to punish Eretria. Prelude When the Eretrians had discovered that the Persian task force was heading to attack them, they had appealed to the Athenians to send reinforcements. The Athenians agreed to this, and instructed the 4,000 Athenian colonists from the nearby Euboean city of Chalcis to aid the Eretrians. These colonists had been planted on Chalcidian land after Athens had defeated Chalcis some 20 years previously. However, when these Athenians arrived at Eretria, they were told by a leading citizen, Aeschines, of the divisions amongst the Eretrians, and he advised them to leave and save themselves. The Athenians followed Aeschines' advice and sailed to Oropus, thus avoiding the fate of the Eretrians. The Eretrians failed to come to a clear plan of action; in Herodotus's words "it seems that all the plans of the Eretrians were unsound; they sent to the Athenians for aid, but their counsels were divided". There were three competing plans - one group wanted to surrender to the Persians, seeking to profit thereby, others wanted to flee to the hills above Eretria, whilst others wanted to fight. However, when the Persians landed in their territory, a consensus was reached not to leave the city but to try to withstand a siege, if possible. Opposing forces Eretrians Herodotus does not estimate numbers for the Eretrians. Presumably, the majority of the citizen body would have been involved in the defence of the city, but the population of Eretria at the time cannot be clearly established. Persians According to Herodotus, the fleet sent by Darius consisted of 600 triremes. Herodotus does not estimate the size of the Persian army, only saying that they