When did Germany officially reunite after the Cold War?

Germany officially reunited on October 3, 1990. This date marks the formal establishment of a unified Germany after decades of division following World War II, during which the country was split into East Germany (the German Democratic Republic) and West Germany (the Federal Republic of Germany).

The significance of this event lies in its implications for European politics and the ending of the Cold War era. The fall of the Berlin Wall in November 1989 symbolized the collapse of Communist regimes in Eastern Europe and was a pivotal moment leading up to reunification. However, the actual political and legal processes required for reunification took several months, culminating in the signing of the reunification treaty and the official merging of the two German states in 1990.

The other options represent key moments in German history but do not reflect the official end of division: 1989 marks the fall of the Berlin Wall, an important precursor to reunification; 1991 represents the dissolution of the Soviet Union, which further impacted Eastern Europe but was after Germany's reunification; and 1992 is too far removed from the events closely associated with the reunification process.