After 1848, when the Wallachian Revolution ended in occupation by Ottoman and Russian troops, and until the Crimean War, Vaillant continued to print pamphlets supporting the Romanian cause. As Russian troops retreated, to be replaced by a provisional Austrian administration, in turn superseded by a protectorate of powers (including the French Empire), he issued text supporting a Moldo-Wallachian union and emphasizing the two countries' autonomy in respect to the Porte. In 1857, he authored an appeal to Count Colonna-Walewski, the French Foreign Minister, in which he called for "France's sympathies" in respect to "the Moldo-Wallachians", based on "their magnificent past and the hope of their future". At the time, he made several references to Romania as "la langue d'or" ("the golden language"), a name notably featured in the title of a Romanian literature collection he printed in 1851. Vaillant also wrote pieces criticizing Moldavian separatists.