The farmer Stanisław Śliwowski lived in Kowalewszczyzna near Białystok. He had many Jewish trading partners. In 1941 the German occupiers began persecuting the local Jews. Śliwowski helped those at risk whenever he could. Since his family members were afraid of being denounced, he could not hide people long-term on his farm. However, he found hiding places for them in the surrounding forests.
In 1943 a young man approached Śliwowski while he was working in his fields. The teenager asked for work and said his name was Wacław Bartkowiak. In fact, he was a 17-year-old Jew named Izaak Kornblum. Although the boy obviously had no experience, Śliwowski gave him work as a shepherd. He found out after some time that Kornblum was Jewish, but did not betray him.
Śliwowski married in 1944. His wife was afraid of being denounced, so he sent Kornblum away. However, he connected him to a group of Jews hiding in the surrounding area, whom Śliwowski supported.
Śliwowski was honored as Righteous Among the Nations by the Israeli Holocaust memorial center Yad Vashem in 1988.