Irakleia — also known as Arakleia and, in the Middle Ages, as Irakleitsa — preserves its ancient name. Important archaeological finds, now exhibited in museums, suggest Irakleia flourished from 3200 B.C. through 1000 B.C., when Cycladic civilization reached its peak.
For long periods, however, the island was abandoned as inhabitants took flight to escape pirate raids. From the late 18th century through 1826, most of the island was infertile and only a few lots (metohia, or dependencies) were cultivated or used for grazing animals for Panayia Hozoviotissa’s monks on Amorgos, as the island was one of the monastery’s assets.
In 1826, small illegal colonies began being formed on the island by migrants from Aegiali, a village on Amorgos. In 1831, the monastery formally allowed migrants from Aegiali to settle on the island, granting them ten -year licenses to occupy and exploit their products in return for a fifty percent share.