These areas have always been German, in fact Pomerania and Brandenburg were both part of Prussia since the 1700's. Why did the Soviet Union do this, and how did the victorious powers justify taking these very German areas away to form Poland? Bear in mind that when borders shift in Europe, the 'shifter' usually has some sort of (usually weak) justification, like Danzig being a former part of Poland-Lithuania and Alsace-Lorraine being a part of the HRE before 1680. However I don't think east Pomerania and east Brandenburg was ever Polish, although Silesia had a Polish minority.

How were these territories acquired? In WW1, German territories were readily carved up by the Treaty of Versailles; what was the treaty in question after WW2?

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    Hum, "[...] ethnically cleansed" is rather offensive. I would suggest rephrasing that part. Aug 2, 2013 at 15:01
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    @Sardathrion: offensive or not, that is exactly what happened.
    – sds
    Aug 2, 2013 at 15:16
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    @Sardathrion: mass expulsion AKA population transfer
    – sds
    Aug 2, 2013 at 15:57
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    As to the addendum: Those areas are probably as likely to be returned to Germany as France, Spain, (most of) Germany, Greece, (most of) England, and many others to be returned to Italy because they were all part of the Roman Empire. ^_~ Aug 2, 2013 at 16:34
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    @PieterGeerkens en.wikipedia.org/wiki/Province_of_Brandenburg Aug 2, 2013 at 22:32

5 Answers 5


Post-World War II Poland was "designed" by the British foreign office, presented by Churchill, and ratified by Roosevelt and Stalin at the Tehran Conference in 1943, as noted in another answer.

After World War I, Britain had planned on the so-called Curzon line for the eastern boundary of Poland (based on the ethnic divisions) but the country crossed that boundary in 1919-20 and seized chunks of Belarus and the Ukraine east of that line from the Soviet Union. The 1939 German-Soviet partition line actually coincided almost exactly with the Curzon line, with minor differences. Hence, it was easy for Britain and the Soviet Union to agree on the final eastern boundary of Poland.

In compensation, Churchill's plan was to restore to Poland land that had been "German" for two or three centuries, but had been Polish earlier in the Middle Ages. These included Silesia and Pomerania. As a practical matter, the new western border was set on the Oder and Neisse rivers, meaning that some small pieces of German (East) Brandenburg east of the line went to Poland, and some small pieces of former Polish Pomerania went to Germany.

Silesia had originally been Polish, was inherited by the heir to the Bohemian crown, and ultimately by Austria, when the Bohemian royal line died out. It was captured by Germany (Brandenburg-Prussia actually), in the War of the Austrian Succession in 1740, which is why it became "German." All this over a period of several centuries.

Pomerania (Polish for on the sea) was originally held by Polish dukes. When they started accruing land west of the Oder in the 12th century, this portion of Pomerania was held as a fiefdom under the Holy Roman Emperor. Eventually, the German influence won out, and all of Pomerania was under the Holy Roman Empire, or one its Electors, that of Brandenburg. During the Middle Ages, there was a certain amount of back-and-forth, but the end result was increasing German settlement and influence on Pomerania, particularly west of the Oder, less so under the east, while nominally under a Polish noble line, the Griffins. When they died out around 1650, Pomerania was divided between Sweden and Brandenburg-Prussia, with the latter eventually absorbing the Swedish portion over the next century or so.

All of the above as justification for the Allies doing what the wanted to do, transfer these lands from Germany (back) to Poland, and the Soviet Union taking back the pieces of Belarus and the Ukraine occupied by Poland.

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    What about East Brandenburg? Aug 2, 2013 at 20:54
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    @SchwitJanwityanujit: Para 3: As a practical matter, the new western border was set on the Oder and Neisse rivers, meaning that some small pieces of German (East) Brandenburg east of the line went to Poland, and some small pieces of former Polish Pomerania went to Germany.
    – Tom Au
    Aug 3, 2013 at 2:11
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    Churchill writes that he was appalled by the amount of German land given to Poland by Stalin.
    – sds
    Aug 4, 2013 at 5:24
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    @Sds: The idea originated with Churchill. But of course, he didn't foresee that Stalin would use that to "take him to the cleaners."
    – Tom Au
    Aug 4, 2013 at 21:59
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    Churchill just planned for the expulsions to cover the exclave of East Prussia and some minor adjustments of the prewar border. Stalin insisted on moving the border as far west as possible.
    – dan04
    Jun 19, 2014 at 14:35


Post-war Polish borders were agreed upon in Teheran (1943) and finalized in Yalta (1945) by the "Big 3".

The land was taken from Germany on the grounds of Germany having started the war, to weaken it so that it would never be able to do that again.


The Poles did not do the ethnic cleansing of those lands singlehandedly - at first the Germans ran away themselves, spurred by Goebbels's wildly exaggerated reports of the Red Army's atrocities (the atrocities were real, but the reports were exaggerated; in fact, there are some indications that the Red Army behaved differently in the areas which were to be given to Poland and Russia than in the areas which were to remain German).

Also, don't forget that Poles were also resettled.


I think one has to look at this episode in context: a horrible war just ended and the leaders set to the task of resolving the tensions which led to the war. The major source of tensions was people of one nationality living on the territory controlled by another (e.g., Germans in Sudetenland). So, to prevent those issues from re-appearing, massive population exchanges were undertaken, to ensure countries' ethnic homogeneity.

While many people suffered in the process, it was still done nicer than the similar attempt by the Germans during the war, and it did ensure that a similar conflict is now highly unlikely.

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    "The major evictions were completed in 1946, although another 500,000 Germans arrived in the Soviet Zone from Poland in 1947" en.wikipedia.org/wiki/… Aug 2, 2013 at 15:20
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    The Polish population transfers article might help as well. Aug 2, 2013 at 15:42
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    "massive population exchanges...to ensure countries' ethnic homogeneity" What a disgusting thing to do. +1 for a good answer, though.
    – Joe
    Aug 2, 2013 at 19:26
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    spurred by Goebbels's wildly exaggerated reports of the Red Army's atrocities This is misleading. The Soviets carried out mass rapes of women and took men for forced labor. Hundreds of thousands of German civilians died in Soviet and Polish camps. Goebbels may have exaggerated, but the reality was pretty bad.
    – user2848
    Aug 3, 2017 at 18:17
  • @BenCrowell: the atrocities were real, but the reports were exaggerated.
    – sds
    Aug 3, 2017 at 18:31

You're right to say that Germany's loss of territory to Poland in 1945 was "harsh" judged by the principle that borders should be delineated according to ethnic and/or historical claims. No one then or since has tried to argue that the areas in question had been anything other than ethnically German for centuries

However Germany in 1945 was not any normal defeated power. It was allowed no voice in the settlement of its borders. Its utter defeat and devastation was of course one reason why it could not contest the settlement. For a long time after May 1945 there simply wasn't a state of Germany either practically or legally. This was one reason why the allied powers dismissed and arrested the Flensburg government (the government which continued to function - after a fashion - after Hitler's death). It emphasised that German statehood was now null and void.

Furthermore, German state or no German state, the victorious powers could justify transferring to Polish control large areas of formerly German territory:

1) Germany was perceived to need weakening so as to limit its capacity to once again renew itself after a defeat and wage aggressive war. In fact still harsher plans had been considered (e.g. the Morganthau plan).

2) The nazi policy of aggressive expansion and the crimes committed against Polish and Soviet civilians eliminated any squeamishness anyone might have had about expelling westwards large German populations.

3) In any case, as the other answer notes, a significant proportion of the local German population had already fled westwards even prior to fixing new borders

4) The idea of "shifting" borders west (the USSR expanding into Poland, Poland being compensated with parts of Germany), in order to create a sizeable safety buffer between the Russian heartland and Germany, was seen as reasonable in the light of Germany's two recent invasions of Russia (1914 and 1941).

You ask which treaties have defined Germany's loss of these territories. Wikipedia's German-Polish 1990 treaty article lists the key ones:

1945: Potsdam agreement
1950: Treaty of Zgorzelec between the DDR and Poland
1970: Treaty of Warsaw
1990: German-Polish Border Treaty


Addition to the answers given so far:

Since the Potsdam treaty (and other agreements between the "Big 3") was not signed by Germany itself, it was not a "real" peace treaty by international law. In fact, it does not declare that the mentioned territories are to be annexed by Poland .. merely occupied until a final peace treaty is signed (with the intention to weaken Germany and create a buffer zone to the Soviet Union, as said in other answers). This probably eased the acceptance of the treaty by the western Allies.

But the issue got a lot more complicated by the fact that two independent German states were founded after the war, one an ally of Poland, and one an enemy. Both sides denied the other the authority to sign a final treaty, delaying this step until 1990, when a reunited Germany could finally close the case once and for all.

Of course, by that time, the territories had been mainly inhabited by Poles for decades (and many former German inhabitants had died), and it was entirely unrealistic that they would be given back. But up until that point, the former German inhabitants of said areas had a reason to claim that they were de jure still German (this point of view was officially supported by the Western German government until 1970). If the Allies had signed a peace treaty with some strawman German representatives straight away in the late fourties, the whole issue would have had much less publicity. But the start of the Cold War got in their way.


Poland was simply ethnically cleansed by the Russians who force marched entire German families out of Silesia into east Germany.

Before there was any civil authority created in Silesia Polish Jews freed from incarceration created their own Freedom committees. For at least the first six months after Germany's capitulation these were the only real authority. These former Kz inmates took over whatever accommodations they wanted.

  • 1
    protoclos of the elders of zion is a great book, right?
    – Bak1139
    Jun 23, 2014 at 10:18
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    Please provide references/citations when you accuse people of criminal behavior (ethnic cleansing). This is just a block of opinion.
    – MCW
    Jun 29, 2015 at 14:18
  • I think that it is inappropriate to make jocular references to the Protocols of the Elders of Zion. Not everyone is aware that the book is offensive, nor that it has been used to justify reprehensible behavior.
    – MCW
    Jun 29, 2015 at 14:19

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