Adolfo Kaminsky was born on Oct. 1, 1925, in Buenos Aires. His parents, Salomon and Anna (Kinoël) Kaminsky, were Russian Jews who met in Paris in 1916. His mother had fled the pogroms in Russia; his father was a journalist for a Jewish Marxist newspaper. When the Bolsheviks overthrew the czarist government, France expelled sympathizers of the new regime, and the Kaminskys fled to Argentina, where their two other sons were also born.
By the early 1930s, the Kaminskys were able to return to France and settle in the town of Vire in Normandy. Adolfo left school at 13 to help an uncle run his market stall, but finding him overbearing, the boy left to work in a factory that made airplane instruments.
The Germans invaded France in 1940. They took over the Normandy factory and dismissed all Jewish workers. Needing work to help his family, Adolfo answered an ad for an apprentice dyer in a business that converted military uniforms and greatcoats to civilian wear. The owner, a chemical engineer, taught him the secrets of altering and removing colors. Adolfo became an expert at effacing the most stubborn stains.
He became so interested in chemistry that he took a side job as an assistant for a chemist at a dairy that churned butter. To gauge the fat content of the cream brought by farmers, the dairy would insert methylene blue in a sample and waited for its lactic acid to dissolve the color. That was how Adolfo learned that lactic acid was the best eraser of Waterman blue ink, the kind used on ID cards.
In 1941, the Kaminskys were arrested and sent to Drancy, an internment camp near Paris that was a way station to the death camps. Thanks to their Argentine passports, they were released after three months.
But the family soon feared that those passports would no longer protect them, and so Adolfo, by then 18, was dispatched to secure documents from the French underground that would disguise the fact that they were Jews. When the resistance agents learned of his expertise, they recruited him.
A memoir, told in his voice but written by his daughter Sarah Kaminsky and published in English in 2016 with the title “Adolfo Kaminsky: A Forger’s Life,” chronicles how Mr. Kaminsky began his resistance work in earnest after learning that his mother had been killed on a train returning from Paris, where she had gone to warn her brother of his impending arrest. Furious, he committed several acts of sabotage, using chemicals to rust railway equipment and corrode transmission lines.