The oblast was organized on 7 August 1940 on the territory, known as Budjak or southern Bessarabia, occupied by the Soviet Union from Romania. It was originally known as Akkerman Oblast () until 1 December 1940, i.e. before the oblast center was moved from Akkerman to Izmail. The oblast was administratively subdivided into 13 raions. On 15 February 1954, the oblast was liquidated, and its territory was included into Odessa Oblast. The current area is now divided into two municipalities (Izmail and Bilhorod-Dnistrovskyi) and nine raions; these cover and in 2015 had a combined population of 592,842.