Germany officially reunifies, NATO membership extends to former East Germany under Two Plus Four constraints

East and West Germany formally reunify on October 3, 1990, creating a single sovereign state for the first time since 1945. Under the Two Plus Four Treaty, unified Germany retains NATO membership, though NATO forces are barred from the former East German territory until Soviet troops complete their withdrawal in 1994. The U.S. maintains roughly 245,000 troops in Germany at reunification — the largest foreign military presence on German soil. The day marks the end of the Cold War's European order and begins a new chapter in U.S.-Germany military relations based on alliance rather than occupation.