Henriette Lucie Strauss was born on May 2, 1870, in Halle, Westphalia, the daughter of Dr. Abraham Strauss, Geheimer Medizinalrat, and his wife Rosa, née Schuler. Her mother had a brother Aaron Schüler, who married Jeanette Kissing. As the youngest of their six children, she gave birth to Elisabeth, later Else Schüler, married

Fritz Mendel was born in Bonn on December 23, 1899, the son of furniture manufacturer Emanuel Mendel and his wife.

Stella Schnitzer was born on May 28, 1894 in Andrichau (today Andrychow/Poland) into a Jewish family.

Salomon Meissner was born in Schildberg/Posen on March 24, 1882, the son of Joseph Meissner and his wife Henriette, née Unger.