The town of Chios is on the east coast, and has a modern harbour, a cathedral and a 13th-century castle. It exports local produce and imports timber products.

Chios was settled by the Ionians towards the end of the Bronze Age. It is first recorded in history as a powerful maritime state having close ties with Miletus, in Asia Minor. They were both taken by the Persians in 546 BC, and when Miletus revolted, Chios sent 100 ships to its aid in 494 BC. The revolt failed, and Chios was again subject to Persia. Some of its vessels were in the Persian fleet at the Battle of Salamis. The state became independent after the Greek victory at Mycale in 479 BC. It joined the Delian League and was for a long time one of the most favoured allies of Athens.

A Genoese chartered company held the island from the 14th century until 1566, when the Turks took it. Except for a brief occupation by the Venetians in 1694, it remained in Turkish hands until World War I, when it became Greek. In 1881 the island was devastated by an earthquake. The revolt that led to the fall of King Constantine in 1922 began in Chios.