It is a small flat province separated from the rest of the country by the Baltic Sea and two European Union and NATO members: Poland to the south and Lithuania to the north and east.

But after defeat in World War II in the mid-20th century the Germans fled or were expelled, and the victorious Soviet Union repopulated the territory, mostly with Russians.

The territory of what is now the Kaliningrad Oblast used to be inhabited by the Old Prussians and other Western Balts, prior to the Teutonic conquest in the early Late Middle Ages.

[14] Afterwards, it was settled by Germans (especially the western part), Lithuanians (especially Lithuania Minor) and Poles (especially Königsberg, Polish: Królewiec, and the current southern border strip).

[16] In 1255, on the foundations of a destroyed Sambian settlement known as Tvanksta, the Teutonic Order founded the city of Königsberg (modern Kaliningrad), naming it in honour of Ottokar II of Bohemia.

[18] The German colonist peasants, craftsmen, and merchants were predominantly concentrated in the southern part of the Teutonic State and did not move into Nadruvia and Skalvia due to the Lithuanian military threat.

In 1454, following a request by the anti-Teutonic Prussian Confederation, the territory was incorporated to the Kingdom of Poland by King Casimir IV Jagiellon,[19] an event that sparked the Thirteen Years' War (1454–1466).

[21] In 1525, Grand Master Albert of Brandenburg secularized the Teutonic Order's Prussian branch and established himself as ruler of the Duchy of Prussia, the first Protestant state in Europe.

[17] Polish and Lithuanian culture blossomed in Königsberg, with the city being the place of publication of the first Polish- and Lithuanian-language cathechisms (by Jan Seklucjan and Martynas Mažvydas), the first Polish translation of the New Testament, Grammatica Litvanica, the first Lithuanian grammar book, and the Albertina University being the second oldest university of the Polish–Lithuanian Commonwealth, after receiving a royal privilege from King Sigismund II Augustus in 1560.

[22] In 1577, the Duke of Prussia forbade serfs—who were mostly Old Prussians, Lithuanians, and Masurians—to leave the land that was the property of the German knights who became proprietary nobles.

[24] In 1724, King Frederick William I of Prussia prohibited Poles, Samogitians and Jews from settling in Lithuania Minor, and initiated German colonization to change the region's ethnic composition.

[34] However, the majority of East Prussian Polish and Lithuanian inhabitants were Lutherans, not Catholics like their ethnic kinsmen across the border in the Russian Empire.

Only in southern Warmia did Catholic Poles—so called Warmians (not to be confused with predominantly Protestant Masurians)—comprise the majority of the population, numbering 26,067 people (~81%) in county Allenstein (Polish: Olsztyn) in 1837.

After 1876, farm prices in East Prussia fell by 20 percent, which encouraged local landowners to hire foreign workers from Congress Poland, incidentally strengthening the Polish element in the region.

Poles and Lithuanians of East Prussia also had much higher birth-rate and natural increase rates than the Germans, and rarely emigrated.

[42] Later, Hindenburg and Ludendorff pushed Russia back at the battle of Tannenberg, thereby liberating East Prussia from Russian troops.

During the last days of the war, over two million people fled, anticipating imminent Red Army conquest, and were evacuated by sea.

[46] Under the Potsdam Agreement of 1 August 1945, the city became part of the Soviet Union pending the final determination of territorial borders at an anticipated peace settlement.

CITY OF KOENIGSBERG AND THE ADJACENT AREAThe Conference examined a proposal by the Soviet Government that pending the final determination of territorial questions at the peace settlement, the section of the western frontier of the Union of Soviet Socialist Republics which is adjacent to the Baltic Sea should pass from a point on the eastern shore of the Bay of Danzig to the east, north of Braunsberg – Goldep, to the meeting point of the frontiers of Lithuania, the Polish Republic and East Prussia.

U.S. president Harry Truman and British prime minister Clement Attlee supported the proposal of the Conference at the forthcoming peace settlement.

[47]In 1946, Königsberg was added as a semi-exclave to the Russian SFSR and renamed Kaliningrad, after the Chairman of the Presidium of the Supreme Soviet of the USSR Mikhail Kalinin.

[52] In the 1950s, Nikita Khrushchev offered the entire Kaliningrad Oblast to the Lithuanian SSR but Antanas Sniečkus refused to accept the territory because it would add at least a million ethnic Russians to Lithuania proper.

This isolation became more severe when both Poland and Lithuania joined NATO and the European Union and imposed strict border controls on Kaliningrad Oblast.

Some of the region's cultural heritage, most notably the Königsberg Cathedral, was restored in the 1990s, as citizens started to examine previously ignored German past.

[73] A few months after the 2022 Russian invasion of Ukraine, Lithuania started implementing EU sanctions, which blocked about 50% of the goods being imported into Kaliningrad by rail.

The reason given for the change is that Mikhail Kalinin, a member of the Soviet Politburo, was among those responsible for the Katyn massacre, having co-signed the order to murder thousands of Polish prisoners of war.

[77] As a semi-exclave of Russia, it is surrounded by Poland (Pomeranian and Warmian-Masurian Voivodeships), Lithuania (Klaipėda, Marijampolė, and Tauragė Counties) and the Baltic Sea.

Major cities and towns include: † Pre-1946 (the German-language names were also used in English in this period) The climate of Kaliningrad Oblast gradually transitions from oceanic to humid continental depending on distance from the Baltic Sea moderation.

The local climate is slightly wetter than similar latitudes farther west, but infrequent ice days lead to low snow accumulation regardless.

[93] Car and truck assembly (GM, BMW, Kia, Yuejin by Avtotor) and the production of auto parts are major industries in Kaliningrad Oblast.