In the sixth century B.C. Icaria was absorbed by Samos and became part of Polycrates sea empire. At this time the temple of Artemis at Nas, on the northeast corner of the island was built. Nas was a sacred spot to the pre-Greek inhabitants of the Aegean, and an important port in the Aegean, the last stop before testing the dangerous Icarian Pelasgian. It was an appropriate place for sailors to make sacrifices to Artemis, who among other functions, was a patron of seafarers. The temple stood in good repair until the middle of the 19th. century when it was pillaged by the villagers of Christos, Raches for marble for their local church. In 1939 it was excavated by the Greek archeologist Leon Politis. During the German and Italian occupation of Icaria in the Second World War many of the artifacts unearthed by Politis disappeared. Local custom has it that there are still marble statues embedded in the sand off the coast.
In the 14th. century A.D. Icaria became part of a Genoese Aegean empire. The Knights of St. John, who had their base in Rhodes, exerted some control over Icaria until 1521 when the Ottoman Empire incorporated Icaria into its realm. The Icarians killed the first Turkish tax collector, but somehow managed to escape punishment.
The Turks imposed a very loose administration not sending any officials to Icaria for several centuries. The best account we have of the island during these years is from the pen of the Bishop J. Georgirnees who in 1677 described the island with 1,000 inhabitants who were the poorest people in the Aegean. In 1827 Icaria broke away from the Ottoman Empire, but was forced to accept Turkish rule a few years later, and remained part of the Ottoman Empire until July 17, 1912 when it expelled a small Turkish garrison during the Icarian struggle for independence. Due to the Balkan Wars, Icaria was unable to join Greece until November of that year. The five months of independence were difficult times. The natives lacked food stuffs, were without regular transportation and postage service, and were on the verge of becoming part of the Italian Aegean empire.
The island suffered tremendous losses in property and lives during the second world war and the German and Italian occupation. There are no exact figures on how many people starved, but in the village of Karavostomos over 100 perished from starvation. After the war the majority of the islanders were sympathetic to communism, and the Greek government used the island to exile about 13,000 communists from 1945 to 1949. The quality of life improved greatly after 1960 when the Greek government began to invest in the infrastructure of the islands assisting in the promotion of tourism.