German Re-unification -East Germany Merge With West Germany Oct 03,1990

German Re-unification - celebrated on Oct 3,1990

German re - unification  was the process in 1990 in which the East Germany(GDR)  joined the West Germany(FRG). 

The start of this process is commonly referred by Germans as '' die Wende '' (The Turning Point). 

The end of the unification process is officially referred to as German unity

A reunification treaty between West Germany(FRG) and theEast Germany(GDR) was negotiated in mid-1990, signed on  Aug 31,1990 and finally approved by large majorities in the legislative chambers of both countries on Sep 20, 1990.East Germany joined the Federal Republic as the five states of Brandenburg,Mecklenburg -Vorpommem,Saxony,Saxony-Anhalt and Thuringia. 

To commemorate the day that marks the official unification of the former East and West Germany on Oct 3,1990 has since then been the official German national holiday, the Day of German Unity.
 It replaced the previous National Holiday held in West Germany on June 17 commemorating the Uprising of 1953 in East Germany and the National Holiday on Oct 7 in the East Germany(GDR)

At Berlin's Brandenburg Gate - Oct 3, 1990