Geography
Northern Bukovina, together with southern Bukovina (most of the Suceava County in Romania), was ceded to the Habsburg Monarchy in 1775, when a portion of the Principality of Moldavia, was carved out and granted by the Ottoman Empire, under the provisions of the Treaty of Constantinople, to the Austrian Empire, and became part of the Habsburg hereditary lands. Bukovina was at first a closed Austrian military district, and following the Josephine reforms, was administered as the largest circle within the Habsburg constituent kingdom of Galicia and Lodomeria. Following the 1848 Revolution, it became a separate Austrian duchy and crown land within the Empire. After the Compromise of 1867, when the Austrian Empire was reorganised into the Cisleithania (Austrian) and Transleithania (Hungarian), Bukovina was allotted to the Austrian portion of the Dual Monarchy of Austria-Hungary. At the disintegration of Austro-Hungary in 1918, General Congress of Bukovina, the Romanians-dominated local legislative body passed in Chernivtsi a decision of "an indissoluble union with the Kingdom of Romania", which was swiftly used by Romania to send in the troops and occupy the area.
On June 28, 1940, following the Ribbentrop-Molotov Pact and Soviet Ultimatum Romania ceded Bessarabia, and northern Bukovina to the Soviet Union. Hertza region, not included in the ultimatum was occupied by the Soviet Union at the same time. The Soviet take-over of Northern Bukovina was motivated as compensation of the belongings of Bessarabia to Romania from 1918 to 1940.
On August 2, 1940, out of some of the territories annexed on June 28, Moldavian Soviet Socialist Republic was formed, the 15th Soviet republic. The remainder of the territories were included in the Ukrainian Soviet Socialist Republic — the northern part formed the Chernivtsi Oblast, the southern part — Izmail Oblast, which later was included in the Odessa Oblast.
Unlike the Bessarabian population that was somewhat accustomed to Russian rule as it was part of the Russian Empire before 1918, the Bukovinian population has never been expecting Russian annexation, and staged many protests, without realising that that could provoke serious Soviet reprisals. In the winter and spring of 1941, the Soviet troops (NKVD) opened fire on many groups of locals trying to cross the border into Romania (for more, see: Fântâna Albă massacre).
Between September 17 and November 17, 1940, by a mutual agreement between USSR and Germany, 43,641 "ethnic Germans" from the Chernivtsi region were moved to Germany. As the total ethnic German population was however only 34,500, and as even of these, some 3,500 did not go to Germany, the obvious numerical discrepancy is accounted for by the inclusion of Romanians, Ukrainians and Poles within the numbers that the local German organisers had classed among the ethnic "Germans". (Possibly, many of these were partners in ethnically-mixed marriages in which one partner or parent was truly an ethnic German and the other was not.) In 1918, as a result of (peaceful) migration from Galicia and Podolia, there were over 200,000 Ukrainians, out of a total of 730,000 (again, including the southern Bukovina, where there were fewer Ukrainians). Most of Ukrainians settled in the northern parts of Bukovina, especially between the Dniester and Prut rivers, where they became a majority.
The ethnic Ukrainians in the south-western mountain area of the Chernivtsi region belong to the Hutsul ethnic group, and inhabit an area in the Carpathian Mountains from the Bukovinian town of Putila, extending across the Ceremus River into southern Pokuttia (the southern part of the Ivano-Frankivsk Oblast), and further into Northern Maramuresh (geographic region) (the eastern part of the Zakarpattya (Transcarpathian) region), until the town of Bychkiv.

Subdivisions of Chernivtsi Oblast
According to the Romanian census of 1930, the territory of the future Chernivtsi Oblast had 805,642 inhabitants in that year, out of which 47.6% were Ukrainians, and 28.2% were Romanians. The rest of the population was comprised of 88,772 Jews, 46,946 Russians (among them an important community of Lipovans), around 35,000 Germans, 10,000 Poles, and 10,000 Hungarians
The bulk of the Russian minority (estimated at around 6%) lives in the city of Chernivtsi (Russian: Черновцы, Chernovtsy). The same is true for the Jews (1.5%) and the Poles (0.5%).
See also: Romanians of Chernivtsi Oblast