The present drawing celebrates the Treaty of Vienna signed on 30 October 1864 between Austria and Prussia on one side and Denmark on the other. The treaty aimed at settling the future of the Duchies of Schleswig-Holstein, which were disputed by Denmark since the death of King Frederick VII, the last heir to the Duchies and the Danish crown. The issue was whether the Duchies were an integral part of Denmark or whether they should revert to a German confederation on cultural grounds. The allegory describes the joint invasion of the Duchies of Austria and Prussia in February 1864.
Lami painted a number of large historical canvases. He had been one of the favourite painters of Louis-Philippe and was commissioned to paint several large pictures for the galleries at Versailles. Lami lost his special position with the ascension of Emperor Napoléon III to the throne, but the present drawing suggests that he still aspired to paint such subjects.