The High Commission in Smyrna was established in May 1919, as soon as the Greek occupation was inaugurated.

The High Commissioner, Aristeidis Stergiadis, appointed by Eleftherios Venizelos, reached Smyrna three days after the landing of the Greek army.
The Treaty of Sevres abolished the Turkish political administration in the territories ceded to Greece. Thus, in July 1920 the protocol of surrender of the city was signed by the replacement of the vali of Aydin before the general secretary of the High Commission and Smyrna passed to Greek administration.

The Greek Administration of Smyrna preserved all the services and institutions dealing with the religious, educational and family affairs of the Muslims.
It restructured the Greek services giving emphasis to public health, the building of churches and schools and the relief of refugees who had been repatriated since 1919.
Considerable work was achieved, especially in the relief and resettlement of the approximately 250,000 Asia Minor refugees who returned to Asia Minor from Greece, where they had sought protection during the persecutions of 1914. Loans were granted, model machine-cultivations were promoted, public works (mostly road construction) were inaugurated, all of which provided employment for the refugees. The progressive health scheme, with its free treatment for all inhabitants, regardless of nationality or religion, was impressive. Lastly, the establishment of an Ionian University was put forward. A leading part was played by the distinguished professor of mathematics at the Univeristy of Berlin, Konstantinos Karatheodoris. The first schools would concern the exploitation of the natural resources of the area: the Agricultural School and School of Physics and Engineering. A lot of attention was paid at the same time to the School of Languages and the Department of Health. The latter, related to the health system, was the only department that began to operate before the Catastrophe.