Jesaja Beek was one of the seven children of Izaak Leon Beek and Matje Mok. His father Izaak was already widowed since 1927 and he himself he passed away in 1935 and was interred in the Jewish Cemetery at Muiderberg.
Jesaja Beek was a commercial agent and pollster and married 30 May 1917 in Amsterda…
Jesaja (ook wel Jacques/Sjaak) genoemd was van 1919 tot 1923 eigenaar van een bedrijf Beek&Cohen, adres: Blauwburgwal 16 Amsterdam. Abraham Cohen (Groningen 1883) was zijn vennoot en Leon Beek, (Jesaja's broer) was eerst de procuratiehouder en vanaf 1923 vennoot en eigenaar.
In addition, a Jokos file (number 1365) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.