Key facts and dates

German-Soviet relations in the 1920s were shaped by mutual interests and a shared desire to challenge the post-First World War international order. The Treaty of Berlin in 1926 marked a significant step in this partnership, building on earlier agreements and fostering both diplomatic and military cooperation during a period of tension in Europe.

Timeline of key events

• 1922 – Treaty of Rapallo establishes diplomatic and economic ties between Germany and the Soviet Union.
• 1925 – Locarno Treaties signal Germany's western-oriented diplomatic stance with guarantees of borders in Western Europe.
• April 1926 – Treaty of Berlin signed, renewing and extending German-Soviet neutrality and trade agreements.
• 1920s-early 1930s – Secret military collaboration sees German officers training in the Soviet Union and joint weapons development.

Background to German-Soviet relations and the Treaty of Rapallo

After the First World War, both Germany and the Soviet Union found themselves as international outcasts, isolated by the victorious Allied powers. This shared status laid the foundation for a partnership that began with the Treaty of Rapallo in 1922, marking the start of a complex relationship driven by mutual benefit rather than ideological alignment.

Foundations of the partnership

• Post-war isolation - Germany, burdened by the harsh terms of the Treaty of Versailles (1919), and the Soviet Union, ostracised due to its communist regime, sought alliances outside the Western-dominated system.
• Treaty of Rapallo (1922) - This agreement normalised diplomatic relations between the two nations, renounced territorial and financial claims, and established economic cooperation, providing a basis for future collaboration.
• Mutual interests - Both powers aimed to counterbalance the influence of Western nations, with Germany seeking to regain strength and the Soviet Union looking for recognition and support in a hostile international environment.

Key provisions and significance of the Treaty of Berlin (1926)

Building on the earlier Rapallo agreement, the Treaty of Berlin, signed in April 1926, formalised and extended the relationship between Germany and the Soviet Union. It represented a renewed commitment to cooperation at a time when Europe was navigating fragile diplomatic arrangements.

Core elements of the Treaty of Berlin

• Pledge of neutrality - Both nations agreed to remain neutral if the other was attacked by a third party, ensuring they would not be drawn into conflicts against each other.
• Trade agreements - The treaty reinforced economic ties, facilitating the exchange of goods and resources, which benefited both economies amidst post-war recovery challenges.
• Diplomatic renewal - It reaffirmed the principles of Rapallo, extending formal recognition and dialogue, which was crucial for two powers often excluded from broader European negotiations.

Significance of the agreement

• Strengthened partnership - The treaty solidified German-Soviet relations, creating a framework for ongoing collaboration during a period of uncertainty in European politics.
• Counterbalance to Western policies - For Germany, it provided an alternative to complete reliance on Western powers, while for the Soviet Union, it offered a foothold in European diplomacy.
• Public signal of cooperation - Unlike the secret aspects of their relationship, this treaty was a public declaration of mutual support, influencing perceptions of both nations on the international stage.

Secret military collaboration between Germany and the Soviet Union

Beyond the public agreements, Germany and the Soviet Union engaged in covert military cooperation throughout the 1920s and early 1930s. This secretive partnership allowed both nations to bypass international restrictions and advance their military capabilities.

Nature of the military collaboration

• Training facilities in the Soviet Union - German military officers trained in Soviet territory, gaining experience in modern warfare tactics away from the watchful eyes of the Allied powers enforcing Versailles restrictions.
• Development of forbidden weapons - Joint projects focused on creating tanks, aircraft, and poison gas - all prohibited for Germany under the Treaty of Versailles - enabling technological advancements for both sides.
• Exchange of expertise - The Soviet Union gained access to German technical knowledge and engineering skills, while Germany used Soviet resources and space to rebuild its military expertise.

Benefits of the secret partnership

• Circumventing Versailles for Germany - This collaboration allowed Germany to maintain and develop a core of skilled officers and modern weaponry, undermining the disarmament clauses of the 1919 treaty.
• Military modernisation for the Soviet Union - The partnership provided the Soviets with critical know-how to enhance their own forces, addressing gaps in their technological and strategic capabilities.
• Mutual strategic gains - Both nations prepared for potential future conflicts by strengthening their military readiness through this hidden alliance, away from international scrutiny.

Political implications and strategic benefits for both powers

The German-Soviet relationship, cemented by the Treaty of Berlin and underpinned by secret military ties, had far-reaching political consequences. It offered both nations strategic advantages while reshaping their positions in European affairs.

Political and diplomatic outcomes

• Diplomatic flexibility for Germany - The relationship gave Germany leverage in negotiations with Western powers, demonstrating that it was not diplomatically isolated and could pursue options in the East if Western relations soured.
• Insurance policy - Maintaining ties with the Soviet Union acted as a safeguard for Germany, ensuring it had allies outside the Western sphere, and for the Soviet Union, it provided a counterweight to Western hostility.
• Enhanced international standing - For both powers, the partnership signalled to the world that they could collaborate effectively, challenging the post-war order and asserting their relevance in global politics.

Strategic advantages

• Germany's recovery - The relationship supported Germany's gradual rearmament and military rebuilding, critical for regaining national strength after the humiliations of Versailles.
• Soviet advancement - Access to German expertise accelerated the Soviet Union's industrial and military development, bolstering its position as a major power despite international exclusion.

Impact on neighbouring countries and tensions with Western policies

While the German-Soviet partnership served the interests of both nations, it created significant unease among other European states and complicated Germany's diplomatic stance. The dual orientation of German foreign policy - balancing East and West - raised questions about its long-term intentions.

Regional concerns and Polish alarm

• Poland's position - Caught geographically between Germany and the Soviet Union, Poland viewed the partnership with alarm, as both nations were revisionist powers seeking to alter post-war borders, potentially at Poland's expense.
• Threat perception - The military collaboration and neutrality pledges heightened fears in Poland and other neighbouring states of a coordinated threat, destabilising the fragile balance in Eastern Europe.

Tensions with Western integration

• Locarno policy conflict - Germany's western-oriented Locarno Treaties of 1925, which aimed to secure borders and improve relations with France and Britain, appeared at odds with the continued eastern focus embodied by the Treaty of Berlin.
• Debates over commitment - Historians and contemporaries debated whether Germany's Soviet connection reflected pragmatic opportunism - a necessary hedge against Western distrust - or revealed a deeper ambivalence about fully integrating into the Western diplomatic framework.
• European unease - Western powers grew wary of Germany's dual approach, interpreting the Soviet ties as evidence of potential unreliability, which strained efforts to stabilise Europe through collective agreements.

This complex web of relations illustrates how the Treaty of Berlin and German-Soviet cooperation were not merely bilateral arrangements but pivotal elements in the broader geopolitical landscape of interwar Europe, shaping alliances, fears, and future conflicts.