On October 21, German Defense Minister Boris Pistorius will inaugurate a naval tactical headquarters on the Baltic Sea, intended as a boost to NATO defense readiness in the region. Germany has the largest NATO navy in the Baltic Sea and, according to the ministry, assumed a regional leadership role on October 1.  The new Commander Task Force (CTF) Baltic headquarters will coordinate naval activities for all NATO allies on the Baltic Sea and maintain an overall picture of the maritime situation. In addition to Germany, 11 other nations are involved: Denmark, Estonia, Finland, France, Britain, Italy, Latvia, Lithuania, the Netherlands, Poland and Sweden.

On social media, many users are expressing outrage and spreading false claims. The DW fact check team investigated one particularly viral claim.

Claim: "This should be a blatant violation of the 2+4 treaty, as it clearly states that no NATO troops may be stationed in East Germany," a user wrote in an X post that has been viewed more than 350,000 times and shared over 2,000 times. The user also quotes the headline of the German Ostsee-Zeitung newspaper: "NATO opens new headquarters in Rostock."

DW fact check: Wrong.

The post suggests that NATO would establish a new base in Rostock under its leadership and with its troops, thereby violating the so-called Two Plus Four Agreement.

This claim is false. No new NATO headquarters will be established in Rostock. An existing command staff at the Rostock Naval Command, which already works together with various countries, will in future perform additional tasks for NATO, a spokesperson for the Ministry of Defense told DW.

According to the Defense Ministry, the Commander Task Force Baltic (CTF Baltic), involves the German Navy working with soldiers from partner countries to collect military and civilian data on the Baltic Sea region and make it available to NATO.

No NATO deployment

It is therefore not a NATO headquarters, but a naval headquarters with multinational participation, Frank Sauer, a political scientiest with the Bundeswehr University in Munich, told DW. "A few staff officers from NATO countries will be serving there alongside the Germans. This is not a deployment of armed forces," says Sauer.

And Carlo Masala, the director of the Center for Intelligence and Security Studies at the Bundeswehr University, told DW that "the command center is a German initiative with the Baltic Sea states, which is not integrated into NATO structures and does not report to the NATO commander."

The Two-Plus-Four Treaty

The Two Plus Four Treaty, officially known as Treaty on the Final Settlement with Respect to Germany, was concluded on September 12, 1990, between the Federal Republic of Germany and the German Democratic Republic (GDR), as well as the four WWII victor: the United States, Soviet Union, United Kingdom and France. It came into force six months later.

Among other things, the treaty regulates the internal and external sovereignty of the united Germany and defines the final borders of the national territory. It also regulates the personnel strength of the German armed forces and the renunciation of the possession of so-called NBC weapons, i.e. nuclear, biological and chemical weapons. The treaty also stipulated the withdrawal of Soviet troops and Germany's right to belong to alliances.

Article 5, Paragraph 1 of the treaty states that, until all Soviet forces have been withdrawn, armed forces of other countries may not be stationed on this territory, nor may other military activities be carried out there. This paragraph therefore refers exclusively to the time before the withdrawal of Soviet troops.

"At the time, it was about security guarantees for the Eastern European states and the USSR," Bernhard Blumenau, a lecturer in International History and Politics at the University of St. Andrews in the UK, told DW. "In 1990, Germany's eastern border was NATO's external border. If NATO troops had been stationed there, this would have posed a much greater potential threat to the then USSR. East Germany was therefore intended to act as a buffer and spare the USSR the 'humiliation' of having Western troops on 'its' former territory. Today, however, NATO's eastern border runs through Finland, Poland and the Baltic states."

"In principle, Germany is sovereign under the Two Plus Four Treaty and can therefore use its armed forces on its territory as it wishes, with a few exceptions regarding nuclear weapons," Blumenau said. As it is a German national headquarters, it does not violate the treaty in any way.

As far as the stationing of NATO troops or missiles in East Germany is concerned, Article 5, Paragraph 3 clearly states: "Foreign armed forces and nuclear weapons or their carriers shall not be stationed in or transferred to this part of Germany."

This is not the case with the new function of the command center in Rostock. It therefore does not violate the Two Plus Four Treaty.

Edited by: Kathrin Wesolowski