Masarek was born into an affluent Czech family of tailors. According to the account of Treblinka survivor Richard Glazar, Masarek had been a lieutenant in the Czechoslovak Army before the outbreak of the Second World War in 1939. Regarding Masarek's early life, Glazar comments that "Rudi was a sort of ‘golden youth’. His had been the world of sports-cars, tennis, country-house weekends, summers on the Riviera." Accounts are divided as to whether Masarek himself was Jewish. According to one account, he was a half-Jew, although others state that he was not Jewish at all. In 1938, after the Austrian Anschluss, he had fallen in love with a girl from Vienna who was Jewish; according to other reports, thought not a Jew himself, he chose to follow his Jewish wife to Theresienstadt concentration camp and later to Treblinka.
Deportation to Treblinka
Masarek was relocated from his home in German-occupied Prague to the Theresienstadt concentration camp on 10 August 1942. From there he was deported to the Treblinka extermination camp on 8 October 1942, where between 870,000 to 925,000 European Jews were murdered. His pregnant wife was murdered in Treblinka's gas chambers upon arrival at the camp. Masarek, on the other hand, was selected by the SS for the small Jewish manual labor force assembled to maintain the camp. According to survivor accounts, blond Masarek was noticed for his physique and "Nordic" appearance upon arrival at Treblinka. Glazar writes, "He has a narrow face, light skin, blond hair cut short, bright blue eyes, the chest and shoulders of a fencer. At the disrobing site his physical appearance had set him apart so dramatically that they couldn't help but pick him out."
Imprisonment at Treblinka
At Treblinka, Masarek was first ordered to work in the work units sorting clothing from transports. Later, he was transferred to Treblinka's tailor shop. Glazar noted that "Rudi's Aryan build and athletic posture caught the attention of the fashionable and sadistic Master SergeantKurt Franz." Masarek's tailoring experience was also partly responsible for his transfer. Eventually, the SS gave Masarek the position of Hofjude, a slightly more privileged group of craftsmen prisoners who were used to maintain specific areas of the camp. There, he was ordered to tend to Barry, Kurt Franz' dog. Glazar reports that " assigned our Rudi the task of overseeing all of Treblinka's animal population." Despite the somewhat special treatment granted to Masarek in Treblinka, survivor accounts reveal Masarek's disturbed emotional health after learning of the deaths of his wife and unborn child. Glazar writes, "nd what about our Rudi? He had family on the other side. Always talked about how she had been pregnant and how much he loved her." Masarek attempted suicide twice. Glazar also implies that Masarek, along with others whose families perished upon arrival at Treblinka, had "no intention of escaping" the camp on the day of the uprising on 2 August 1943.
Treblinka prisoner uprising
Much like the subsequent Sobibor extermination camp uprising, a group of Treblinka inmates planned and successfully staged an uprising and escape into the nearby forests. The uprising occurred on 2 August 1943. Masarek assumed an integral military role in the preparations and execution of the uprising. During the uprising, Jewish inmates used SS weaponry to stave off the SS and Ukrainian guards' counterattack while prisoners broke through the camp's fences. In the process, the inmates set many of Treblinka's wooden buildings on fire. According to one account, Masarek was witnessed shooting SS officers from a roof, shouting "This is for my wife and my child who never saw the world!" Masarek died in Treblinka on the day of the uprising. In the months following the uprising, Nazi authorities issued Sonderaktion 1005, the code name for the Nazis' efforts to remove evidence of genocide and other atrocities. As part of the effort, the Nazis dismantled Treblinka's buildings and leveled its grounds. No further information about the fate of Masarek's other family members has been found.
