When the mass arrest of more than 13,000 Jews, the Vel' d'Hiv Roundup, was carried out in Paris on 16 July 1942, Léon's parents sent him and his two brothers into hiding with a neighbour.
His mother and two brothers were held at the Pithiviers and Drancy transit camps, and deported to Auschwitz on 19 August 1942.
Goldberg was known within the resistance under the pseudonym "Julien", and his false papers were in the name of "Gérard Charton".
On 21 October 1943 Goldberg, Boczov, Maurice Fingercwajg, Jonas Geduldig (called "Martiniuk"), Thomas Elek and a sixth resistance fighter, all from the MOI, left on a mission to stop a German convoy on the Paris-Troyes line at Grandpuits near Mormant.
Goldberg was arrested at Mormant, and shot at the fort Mont Valérien on 21 February 1944 with the other members of the Affiche rouge.