When the Kingdom of Italy was restored, they remained under formal Italian possession (under British occupation) until they were ceded to Greece in 1947 under the Treaty of Paris.

[4] Following the end of World War I, Italy agreed twice, in the Venizelos–Tittoni agreement of 1919 and the Treaty of Sèvres in 1920, to cede the islands to Greece except for Rhodes, which would enjoy extensive autonomy.

[5] Italian interest in the Dodecanese was rooted in strategic purposes, and the islands were intended to further the Empire's long range imperial policy.

[5] In 1929, scholarships at the University of Pisa for Dodecanesian students were promoted to disseminate Italian culture and language among the local professional class.

[5][7] While under Lago the inhabitants were allowed to elect their own mayors, in 1937 the fascist system was set up to[clarification needed] the islands, with a newly appointed podestà for each municipality (comune)[7] in 1938, Italian Racial Laws were introduced to the islands along with a series of decrees equalizing local legislation with Italian law.

[7] Mussolini wanted to transform the islands into showcases of the Italian colonial empire, and undertook a series of massive public works in the archipelago.

[10] Mussolini stated that Rhodes had merely returned to its ancestral home after being annexed by Italy, as the Dodecanese had been an important part of the Roman Empire.

[6][10] After the Battle of Greece, Fascist authorities pushed for the incorporation of the Cyclades and Sporades into Italy's Aegean possessions, but the Germans were opposed to any territorial reduction of the puppet Hellenic State.