The treaty supplanted the 1945 Potsdam Agreement: in it, the Four Powers renounced all rights they had held with regard to Germany, allowing for its reunification as a fully sovereign state the following year.

[1][2][3] Additionally, the two German states agreed to reconfirm the existing border with Poland in the German–Polish Border Treaty, accepting that German territory post-reunification would consist only of what was presently administered by West and East Germany—renouncing explicitly any possible claims to the former eastern territories of Germany including East Prussia, most of Silesia, as well as the eastern parts of Brandenburg and Pomerania.

The overall "German Question" became one of the salient and crucial issues of the long-running Cold War, and until it ended in the late 1980s, little progress had been made in the establishment of a single government of Germany adequate for the purpose of agreeing to a final settlement.

[4]: 42–43 Several developments in 1989 and 1990, collectively termed Die Wende and the Peaceful Revolution, led to the fall of the Berlin Wall and the collapse of the SED party in East Germany (GDR).

In a 9 February 1990 conversation with Mikhail Gorbachev held in Moscow, US Secretary of State James Baker argued in favor of holding the Two-Plus-Four talks.

[7] On 18 March 1990, a national election was held in the GDR, leading to an alliance of parties that favored German reunification winning a plurality.

The German government subsequently recognized the Russian Federation's claim to be the successor state of the Soviet Union, including the right to maintain troops in Germany until the end of 1994.

However, with post-Soviet Russia facing severe economic hardship, President Boris Yeltsin ordered Russian troop deployment in Germany to be reduced to levels significantly below those permitted in the Treaty.

By 1 July 2011, the date on which Germany voluntarily suspended conscription, the Bundeswehr retained fewer than 250,000 active duty personnel – barely two thirds of the country's treaty limit.

[14] NATO ended up expanding to sixteen Eastern countries (apart from the GDR in 1990): Czech Republic, Hungary, and Poland in 1999; Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, and Slovenia in 2004; Albania and Croatia in 2009; Montenegro in 2017; North Macedonia in 2020; Finland in 2023; and Sweden in 2024, five of them on the border with Russia.

On 18 February 2017, Russia's Minister of Foreign Affairs, Sergey Lavrov, said he supported the resumption of military cooperation with the NATO alliance.

[21][26][27] His main aide in these negotiations, Eduard Shevardnadze, likewise agreed that NATO never made any such commitment regarding other countries in Eastern Europe, and that "the question never came up" in the talks on German reunification.

[30][31] Gorbachev and his successor, Boris Yeltsin, felt that NATO's later acceptance of countries like Poland violated the spirit of the earlier agreements.

In 2018, Hannes Adomeit disputed the conclusions by Blanton and Savranskaya, saying that those documents were already known, and that,[34] it is inadmissible to conclude that assurances concerning the expansion of NATO command structures and the stationing of NATO forces on the territory of the former GDR had anything to do with promises concerning the enlargement of the Alliance east of a unified Germany.Additionally, he stated that,[34] a distinction must be drawn between informal or exploratory talks of this nature on the one hand and negotiations, promises, commitments or indeed guarantees on the other.An analysis by Marc Trachtenberg in 2021 concluded that "the Russian allegations are by no means baseless ...

"[35][36] In her 2021 book Not One Inch: America, Russia, and the Making of the Cold War Stalemate, Mary Elise Sarotte balanced out these different interpretations, concluding that Russian claims of betrayal are in fact untrue in law but have psychological truth.

[37] On 18 February 2022, German magazine Der Spiegel published an investigation of the British National Archives in which Joshua Shifrinson (Boston University) discovered a memo classified as "secret" dated 6 March 1991 (approximately five months after the 2+4 negotiations).

According to the memo, Jürgen Chrobog, the Western German representative,[38] stated that "during the 2+4 negotiations we made it clear that we [Germany] would not expand NATO beyond the Elbe [sic].