Those of us who (after surviving Terezin and Auschwitz) returned home to
the Czech lands in May 1945 were terrified when the question of who was Czech,
German or Jewish in the 1930 general census was raised. The 1930 census (the year that
I was born) became public. The threat of deportation to Germany after the
war became a possibility (for those declaring themselves German in the 1930
I do not believe that any Holocaust survivors were actually deported (as
were 3million Germans) but the fear was there.
Most younger Jews declared as Czech, but many declared as Germans in the
"secret" 1930 census.