Ionian Islands (region) party. Ionian Islands (region) The Ionian Islands Region (, , ) is one of the thirteen administrative regions of Greece. The administrative region does not include all of the Ionian Islands; the island of Kythera, which historically was part of the island group, was separated and integrated to the (far away) Attica Region. The population of the Ionian Islands in 2011 was 207,855, decreased by 1,50% compared to the population in 2001. Nevertheless, the region remains the third by population density with 90.1/km² nationwide, well above the national of 81.96/km². The most populous of the major islands is Corfu with
United States of the Ionian Islands and Russia signed the Treaty of London, pledging the transfer of sovereignty to Greece upon ratification; this was meant to bolster the reign of the newly installed King George I of Greece. Thus, on 28 May, by proclamation of the Lord High Commissioner, the Ionian Islands were united with Greece. According to the second constitution of the republic (1803), Greek was the primary official language, in contrast to the situation in the Septinsular Republic. Italian was still in use, though, mainly for official purposes since the Venetian Republic. The only island in which Italian (Venetian) had a wider spread was