Johanna Landsberg was born in Berlin on December 26, 1891, the daughter of the merchant Siegmund Landsberg and his wife Bertha, née Oppenheim.

Hermann Wechsler was born Hersu Avram (Hermann Abraham) Vecsler on December 27, 1887 in Botosani, Romania.

Therese Freund was born into a Jewish family in Neersen near Mönchengladbach on August 29, 1871.

Therese von der Wall was born in Norden on February 20, 1879, the daughter of the butcher Heymann von der Wall and his wife Hannchen née Cossen. Her brother Julius was born in 1876, her sister Sophie in 1883.