Wallpainting conservation in Czechoslovakia and Hungary developed from the 19th century to the present day in several stages. The interest of 19th century Romanticism in national culture incited historians of that period to uncover wall paintings. Many of the paintings, damaged over the centuries, has been previously covered by plaster and whitewashed. After uncovering them, the late 19th century painters added the missing and damaged details and whole figures, using in their work cleaning and fixing chemicals without any knowledge of their harmful effects. The 19th century methods, subsequent development, and the consequences for current restoration are described.