Miletus was an ancient Greek city on the western coast of Anatolia, near the mouth of the Maeander River in ancient Ionia. Its ruins are located near the modern village of Balat in Aydin Province, Turkey. Before the Persian rule that started in the 6th century BC, Miletus was considered among the greatest and wealthiest of Greek cities.

Evidence of first settlement at the site has been made inaccessible by the rise of sea level and deposition of sediments from the Maeander. The first available evidence is of the Neolithic. In the early and middle Bronze Age the settlement came under Minoan influence. Legend has it that an influx of Cretans occurred displacing the indigenous Leleges, and the site was renamed Miletus after a place in Crete.

Recorded history at Miletus begins with the records of the Hittite Empire, and the Mycenaean records of Pylos and Knossos, in the Late Bronze Age. Miletus was a Mycenaean stronghold on the coast of Asia Minor from c. 1450 to 1100 BC.

The 13th century BC saw the arrival of Luwian language speakers from south central Anatolia calling themselves the Carians. Later in that century other Greeks arrived. The city at that time rebelled against the Hittite Empire. After the fall of that empire the city was destroyed in the 12th century BC and starting about 1000 BC was resettled extensively by the Ionian Greeks. Legend offers an Ionian foundation event sponsored by a founder named Neleus from the Peloponnesus.

The Greek Dark Ages were a time of Ionian settlement and consolidation in an alliance called the Ionian League. The Archaic Period of Greece began with a sudden and brilliant flash of art and philosophy on the coast of Anatolia. In the 6th century BC, Miletus was the site of origin of the Greek philosophical (and scientific) tradition, when Thales, followed by Anaximander and Anaximenes (known collectively, to modern scholars, as the Milesian school), began to speculate about the material constitution of the world, and to propose speculative naturalistic (as opposed to traditional, supernatural) explanations for various natural phenomena.

By the seventh century B.C.E. the Ionians seem to have made Miletus a prosperous commercial center having numerous colonies on the Black Sea and in Egypt. The woolen goods of Miletus became widely known. Indicative of this is the fact that at Ezekiel 27:18 the Greek Septuagint lists "wool from Miletus" as an item of Tyre's trade. Miletus was also the home of famous philosophers such as Thales, regarded as the founder of Greek geometry, astronomy, and philosophy. In the fifth century B.C.E. the Persians captured and destroyed Miletus for having shared in revolt. Later (in 334 B.C.E.), the rebuilt city fell to Alexander the Great. During Hellenic and Roman times Miletus witnessed considerable architectural activity. An impressive ruin from this period is a large theater built in an open field.

As time passed, the city declined in importance. This is attributed to the silting up of its harbor facilities by the Maeander River. Ancient Miletus seems to have been situated on a promontory extending from the S side of the Latmian Gulf. But today the ruins of the city lie about 8 km (5 mi) inland, and what was once the gulf is a lake.

It was to Miletus that the apostle Paul came, in about 56 C.E. Because of wanting to get to Jerusalem by Pentecost if at all possible and not wishing to spend time unnecessarily in Asia Minor, Paul, apparently at Assos, decided to take a vessel that bypassed Ephesus. But he did not neglect the needs of the congregation there. From Miletus, doubtless by means of a messenger, Paul sent for the older men of the Ephesus congregation, about 50 km (30 mi) away. The additional time it took for word to reach them and for them to come to Miletus (perhaps a minimum of three days) apparently was less than might have been involved had Paul gone to Ephesus. Possibly this was because the available ship(s) from Assos putting into port at Ephesus made more breaks in the voyage than did the one(s) stopping at Miletus. Or, circumstances in Ephesus itself might have delayed Paul had he stopped there.

In speaking to the older men of the Ephesus congregation, Paul reviewed his own ministry among them, admonished them to pay attention to themselves and to the flock, alerted them to the danger of "oppressive wolves" entering the congregation, and encouraged them to stay awake and to keep in mind his example. Having been told that they would see him no more, these overseers gave way to considerable weeping, "fell upon Paul's neck and tenderly kissed him," and then conducted him to the boat.

At an unspecified time after his first imprisonment in Rome, Paul seems to have returned to Miletus. Trophimus, who had earlier accompanied him from Miletus to Jerusalem, became ill, necessitating Paul's leaving him behind.