Ernst David Hellinger
Ernst David Hellinger (* September 30th 1883 in Striegau, † March 28th 1950 in Chicago) He grew up in Breslau, attended school and graduated from the Gymnasium there in 1902. When he was studying at the Gymnasium, he became fascinated in mathematics, due to excellent mathematics teachers at the school.
The Fact his family was Jewish meant that he would have major problems after the Nazis came to power.
1914 marked the start of World War I and Hellinger was involved in war service. However, after the end of the war, there were a number of further important appointments to Frankfurt which built up an impressive mathematics department there. Epstein was appointed in 1919, Dehn in 1921 and Siegel in 1922. Others such as Toeplitz were frequent visitors to the Frankfurt Mathematics Seminar.
On 30 January 1933 Hitler came to power and on 7 April 1933 the Civil Service Law provided the means of removing Jewish teachers from the universities, and of course also to remove those of Jewish descent from other roles. All civil servants who were not of Aryan descent (having one grandparent of the Jewish religion made someone non-Aryan) were to be retired. However, there was an exemption clause which exempted non-Aryans who had fought for Germany in World War I. Hellinger certainly qualified under this clause and this allowed him to keep his lecturing post in Frankfurt in 1933.
Hellinger, however, was forced to retire in 1936 because by this stage the rules that non-Aryans who served in World War I were allowed to keep their posts was being ignored after decisions at the Nuremberg party congress in the autumn of 1935. Hellinger continued to live in Frankfurt. On the Kristallnacht the Gestapo did not arrest Hellinger that night because there was nowhere else to put prisoners.
On 13 November 1938 he found out how far the authorities would go. He was arrested, first taken to the Festhalle and then put into Dachau concentration camp. By this time his sister, Hanna Meissner, was in the United States and she and some friends were able to arrange a temporary job for Hellinger at Northwestern University at Evanston in the United States. He was released from the Dachau camp after six weeks on condition that he emigrate immediately.