Megabates was a Persian general and admiral in the late 6th and early 5th centuries BC. He is most notable under the writings of Herodotus

Herodotus

Herodotus was an ancient Greek historian who was born in Halicarnassus, Caria and lived in the 5th century BC . He has been called the "Father of History", and was the first historian known to collect his materials systematically, test their accuracy to a certain extent and arrange them in a...

 for his joint participation in the failed 499 BC siege of Naxos

Siege of Naxos (499 BC)

The Siege of Naxos was a failed attempt by the Milesian tyrant Aristagoras, operating with support from, and in the name of the Persian Empire of Darius the Great, to conquer the island of Naxos...

. He was sent by Darius the Great alongside Aristagoras

Aristagoras

Aristagoras was the leader of Miletus in the late 6th century BC and early 5th century BC.- Background :Aristagoras served as deputy governor of Miletus, a polis on the western coast of Anatolia around 500 BC. He was the son of Molpagoras, and son-in-law of Histiaeus, whom the Persians had set up...

 and 200 ships to annex the small Aegean Sea

Aegean Sea

The Aegean Sea[p] is an elongated embayment of the Mediterranean Sea located between the southern Balkan and Anatolian peninsulas, i.e., between the mainlands of Greece and Turkey. In the north, it is connected to the Marmara Sea and Black Sea by the Dardanelles and Bosporus...

 island to the growing Persian Empire

Achaemenid Empire

The Achaemenid Empire , sometimes known as First Persian Empire and/or Persian Empire, was founded in the 6th century BCE by Cyrus the Great who overthrew the Median confederation...

.

According to one school of thought, it was in fact Megabates who forewarned the Naxians of the ensuing Persian siege. As a result, Naxos

Naxos (island)

Naxos is a Greek island, the largest island in the Cyclades island group in the Aegean. It was the centre of archaic Cycladic culture....

gathered supplies and fortified their city to withstand the four-month-long siege. It is believed that Megabates' rationale was to shame Aristagoras in the Persian court, for they were earlier during the sail involved in a dispute.

Sources