Gabriel Swart was the eldest child of Marcus Swart and Betje van Beezem. He was born at 51 Joden Houttuinen in Amsterdam. He sold used clothes and scrap metal. On 3 June 1925 he married Lea Wijnschenk, daughter of Abraham Wijnschenk and Aaltje Arbeid.
The couple had nine children: Betje, Aaltje, the twins Abraham and Marcus, Sara, Margaretha, Hartog, Mathilda and Nathan.
After they married, the couple settled at 23 Korte Houtstraat in Amsterdam. In Amsterdam, the family subsequently lived at 66 Joden Houttuinen, 33 Zwanenburgwal, 261 Vrolikstraat, 201 Vrolikstraat and, during World War II, 13 Nieuwe Amstelstraat.
During a raid in April 1943, the family members were removed from their home and deported to Sobibor via Auschwitz.
Copies remain of the birth certificate of Gabriel Swart, the marriage certificate of Gabriel Swart and Lea Wijnschenk, the ketubah from their chuppah and the birth certificates of their children Betje, Aaltje, Abraham, Marcus, Sara, Margaretha, Hartog, Mathilda and Nathan.
In addition, a Jokos file (number 51306) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.