Clara Hammelburg was a daughter of Abraham Salomon Hammelburg and Betje Jacob Speijer. At the age of 18, she married the 19-year old Jacob Houtkruijer on 12 December 1877 in Amsterdam, a diamond polisher and pedlar, a son of Joseph Simon Houtkruijer and Beletje Isaac de Leeff.
Clara’s first husband Jacob Houtkruijer was enrolled 12 March 1878 for military service and incorporated in the 7th Regiment Infantry 7 May 1878, but after five years of service, he was discharged honourably from the military. However after more than one year later, Jacob Houtkruijer passed away 22 October 1884 in his house at Jodenhouttuinen 29 in Amsterdam. As far as has been researched, Clara and Jacob had no offspring.
On 24 December 1890, Clara Hammelburg remarried in Amsterdam, aged 31 years to the 34-year old widower Meijer Leidensdorff from Den Haag, a son of Joseph Leidensdorff and Klaartje de Beer. The couple had two children, namely Hessel in 1891 and Abraham in 1896.
Clara’s 2nd husband Meijer Leidensdorff was previously married on 17 November 1880 to the ±21-year old Saartje Jacobs from Amsterdam, a daughter of Hessel Jacobs and Rachel Swaab. After their marriage Meijer and Saartje lived in Amsterdam and had three children, namely Keetje in 1882, Rachel in 1884 and Joseph in 1886. Saartje Jacobs however passed away 24 December 1889 and was interred in the Jewish Cemetery in Muiderberg.
Since their wedding in 1890, Clara and Meijer lived among others at Waterlooplein 91, Jodenbreestraat 11, Nieuwendijk 119, Oude Schans 92 and since 6 May 1913 at Nieuwe Herengracht 79. There Meijer Leidensdorff passed away 16 February 1919 and interred two days later in the Jewish Cemetery in Muiderberg.
After the passing of her husband, Clara Hammelburg still remained living till 1934 at Nieuwe Herengracht 79; she moved to Scheldestraat 56 on 1 May 1934 and lived in with her son Abraham. When he moved to Nieuwendijk 113 on 6 September 1937, Clara moved again with him too. 21 February 1938 she went living in at the address Vechtstraat 50 ground floor in Amsterdam and 28 February 1942, her last known address became Plantage Franschelaan 11.
From Plantage Franschelaan, Clara Hammelburg was deported to Westerbork 3 February 1943 and from there put on transport to Auschwitz 9 February. On arrival there 12 February 1943, she was immediately killed.
Sources: website wiewaswie, wedding Houtkruijer/Hammelburg; militairy registers of conscripts Amsterdam; website zoekakten.nl, death certificate 8944 of 23 October 1884 for Jacob Houtkruijer; marriage Hammelburg/Leidensdorff; website maxvandam, family trees of Jewish Families, Meijer Leidensdorff/Saartje Jacobs; website Akevoth/Mokum/burialpermits-Meijer Leidensdorff; City Archive of Amsterdam, family registration card of Meijer Leijdensdorff and archive card of Clara Hammelburg; the file cabinet of the Jewish Council, registrationcard of Clara Leidensdorff-Hammelburg.