In 1916, in the middle of World War I, the German military conducted the Judenzählung: a census of German Jews. It was intended to confirm accusations of lack of patriotism among German Jews. But the census not only disproved the anti-Semitic rumors, it crushed them. Not only were German Jews enlisting in the army, a higher percentage of German Jews fought than of any other ethnic, religious or political group in Germany.
The results of the census were not made public at the time.