David was the second of four children born to religious Jewish parents in Kozienice, a town in southeastern Poland. His father, Manes, owned a shoe factory that supplied stores throughout the country. His mother, Sarah, took care of the home and children, and helped in the factory. Kozienice had a thriving Jewish community that constituted over half of the town's population.
1933–39: For most of the 1930s, David spent his days going to school, playing sports, and working in his father's shoe factory. His life, however, changed dramatically in September 1939, when German troops invaded Poland. During the bombing of Kozienice, the Bayers escaped to the forest. They returned to find that German soldiers had looted their home. The Nazis quickly began to implement their antisemitic policies. Jewish homes were marked with the Star of David, a curfew was established, and businesses, like the Bayers', were confiscated.
1940–45: In 1940, the Bayers were forced to move into the Kozienice ghetto, where they were assigned one room. Like other Jews there, David was conscripted to digging irrigation canals. In September 1942, the ghetto was liquidated and its inhabitants, including members of his family, were deported to the Treblinka killing center. David was transported to Pionki, an industrial complex that produced munitions. In 1944 he was deported to Auschwitz, where he was selected for forced labor and transferred to the subcamp of Jaworzno to work in the coal mines. As the Soviet army neared, David and the other prisoners were sent on a death march. SS guards shot prisoners who were too weak to go on or who fell. After stopping at the Blechhammer camp, David escaped into the forests, where he was found five or six days later by Soviet troops. He weighed 70 pounds. He spent two years in the Foehrenwald displaced persons camp in Germany before immigrating to Panama.
In 1948 he left Panama to fight in the Israeli War of Independence. He later immigrated to America and now works as a volunteer at the United States Holocaust Memorial Museum.