Louis van Velzen was a son of Barend van Velzen and Rebecca Viskoper. He married Sara Halberstadt, a daughter of Noach Halberstadt and Esther Klijnkramer.
Louis van Velzen was deported from Mechelen to Auschwitz with Convoy XV, departure 24 October 1942 which arrived in Auschwitz on 26 October 1942. There, at some point, he lost his life there.
Memorial of the Deportations of the Belgian Jews, Dos…