Event

Germany Invades Poland

Germany's invasion of Poland opened the European war and triggered the alliance commitments that turned a regional assault into World War II.

Status: draft
Event Kind: invasion
Date Precision: day
Date Display: 1 Sep 1939
Start Date: 1 Sep 1939
End Date: 1 Sep 1939

What happened

German forces attacked Poland by land and air, beginning a campaign built around rapid operational concentration and coordinated assaults.

Why it matters

The invasion marked the formal opening of the European phase of the war. It converted the unresolved crisis of the interwar order into a general great-power conflict when Britain and France declared war on Germany.

Notes

Use this as the opening military-political anchor for the timeline.