Yos Vainer was born in 1924 in the city of Vinnitsa (Ukraine). After finishing eight classes of Yiddish school, he took accounting courses. In early July 1941, following the outbreak of the Soviet-German War, he and other high school students were sent to the town of Uman, to help with the harvest. On July 19, the Nazis occupied Vinnitsa, and the front line was rapidly approaching Uman. The group of high schoolers had to go further east, to Voroshilovgrad (present-day Luhansk). By the time they arrived there, the frontline had moved once again, and was now only five kilometers from the city. Many of the students went back to Vinnitsa, and only the Jewish ones decided to stay with the retreating troops, being aware of the Nazi anti-Jewish policy. This decision saved Yos Vainer's life: All the Jews of Vinnitsa who had found themselves under German occupation, including his relatives, were shot dead, mostly in mid-September 1941 and mid-April 1942.
The Soviet troops retreated eastward. A month later, when Yos and his fellow students got to Kharkov, the Nazis were already very close to it. Yos and the other members of his group boarded a freight train at the Kharkov railway station, and managed to travel further into the Soviet interior. In late November, they arrived in Penza (a city southeast of Moscow). Yos stayed there until February 1942, when he officially enlisted in the Red Army. He was then assigned to a rifle division, and began to take part in military operations near Moscow.
In his very first assault, Yos was wounded and sent to Moscow for medical treatment. In the summer of 1942, he was discharged from the hospital, and went on to briefly study at the Mikhail Frunze Infantry School (at the Department of Reconnaissance). From September 1942 to December 1943, he served as a scout on the 2nd Ukrainian Front. In December 1943, Yos was seriously wounded again, and treated at a hospital in Akmolinsk (present-day Astana, Kazakhstan). After being discharged, he returned to his division and headed a group of scouts. On several occasional, Yos Vainer and his team carried out assignments to capture German informants. For this, he was awarded two Orders of the Red Star and two Orders of the Patriotic War.
In 1944, Yos Vainer was wounded yet again, in the battles on the Belorussian Front, and in January 1945 he was discharged from the army.
He returned to his native city of Vinnitsa, and worked at a nearby collective farm until 1985.
