The Nazi-Soviet non-aggression pact, signed in August 1939, paved the way for Hitler and Stalin to invade Poland and claim Polish territory.
“The Government of the German Reich and the Government of the Union of Soviet Socialist Republics, desirous of strengthening the cause of peace between Germany and the USSR, have reached the following agreement:
The two contracting parties undertake to refrain from any act of violence, any aggressive action, or any attack on each other, either individually or jointly with other powers.
Should one of the contracting parties become the object of belligerent action by a third power, the other contracting party shall in no manner lend its support to this third power.
The governments of the two contracting parties will in future maintain continual contact with one another for the purpose of consultation in order to exchange information on problems affecting their common interests.
Neither of the two contracting parties will join any grouping of powers whatsoever that is directly or indirectly aimed at the other party.
Should disputes or conflicts arise between the contracting parties over problems of one kind or another, both parties will settle these disputes or conflicts exclusively by means of a friendly exchange of views or, if necessary, by the appointment of arbitration commissions.
The present Treaty shall be concluded for a period of ten years with the proviso that, in so far as one of the contracting parties does not denounce it one year prior to the expiration of this period, the validity of this Treaty shall be deemed automatically extended for another five years.
1. In the event of a territorial and political transformation in the territories belonging to the Baltic States (Finland, Estonia, Latvia, Lithuania), the northern frontier of Lithuania shall represent the frontier of the spheres of interest of Germany and the USSR…
2. In the event of a territorial and political transformation of the territories belonging to the Polish state, the spheres of interest of Germany and the USSR shall be bounded approximately by the line of the rivers Narew, Vistula and San…
4. This Additional Protocol will be treated by both parties as strictly secret.”
Signed in Moscow
August 23rd 1939