West Germany was the informal but almost universally used name for the Federal Republic of Germany from 1949 until 1990, during which years the Federal Republic did not yet include East Germany. Since the German reunification of 1990, the Federal Republic of Germany is informally called simply Germany.
The Federal Republic was proclaimed May 23, 1949, with Bonn as its capital, and included the post-World War IIUK, US, and French occupation zones. West Germany was declared "fully sovereign" May 5, 1955, although with the former occupying troops remaining on the ground, like the SovietRed Army remained in East Germany.
West Germany joined NATO on May 9, 1955, thus becoming a focus of the Cold War with its juxtaposition to East Germany, a member of the subsequently founded Warsaw Pact. The former capital, Berlin, was also divided into East Berlin and West Berlin but West Berlin was completely surrounded by East Germany.
After the fall of the Berlin Wall on November 9, 1989, the unification of the two Germanies was quickly arranged: formally, the Federal Republic of Germany grew by annexing the territory of East Germany, and is now known simply as Germany. This took place on October 3, 1990, and the four occupying powers officially withdrew on March 15, 1991.
This second German democracy was to be a functioning parliamentary democracy with a strong Federal Chancellor, who could only be toppled by a “constructive vote of no confidence”, i.e., by a successor being voted, and a Federal President who played a nominal role only.
While the West of Germany drew “anti-totalitarian” conclusions from the most recent German history, the East, that is the Soviet zone of occupation and later East Germany, had to put up with “anti-fascist” consequences.
The philosopher Hermann Lübbe referred to this approach to recent history as “communicative refusing to mention” (and judged it to be necessary in the stabilizing of WestGerman democracy).