# Soviet and German invasion of Poland

> Live situation record from CLSTR: https://clstr.news/situations/soviet-and-german-invasion-of-poland
> Updated: 2026-10-01T18:15:09.000Z. Sources: 4. Developments: 2.

The 1939 invasion of Poland by Nazi Germany and the Soviet Union initiated World War II and led to the partition of the country. Following the German invasion on September 1, the Soviet Red Army invaded on September 17, an action that resulted in the loss of Polish independence and the internment of the national government in Romania.

The occupation was characterized by systematic terror and the division of Central and Eastern Europe under the Ribbentrop-Molotov Pact. Historical accounts highlight the execution of Polish elites, such as the massacre of approximately 22,000 officers in locations including Katyn Forest, Kharkiv, and Mednoye. The period also saw the establishment of concentration camps and mass deportations by Soviet forces, while the Polish countryside became a site of both pacification and partisan resistance.

## Timeline

### 2026-10-01: Poland marks 87th anniversary of World War II outbreak

Commemorating the 87th anniversary of WWII, historical accounts detail the 1939 invasion of Poland by Germany and the USSR, the subsequent occupation, and the strategic role of East Prussia.

2 sources. https://clstr.news/cluster/poland-marks-87th-anniversary-of-world-war-ii-outbreak-1

### 2026-09-17: Soviet Union invasion of Poland on September 17, 1939

On September 17, 1939, the Soviet Union invaded Poland, leading to the country's partition by Germany and the USSR and the subsequent loss of Polish independence.

2 sources. https://clstr.news/cluster/soviet-union-invasion-of-poland-on-september-17-1939

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Cite as: Soviet and German invasion of Poland. CLSTR, https://clstr.news/situations/soviet-and-german-invasion-of-poland