In 1864 the Austrian Archduke Ferdinand Maximilian Joseph of Hapsburg was invited to the Mexican throne. Genuinely believing he had the backing of the Mexican people Maximilian accepted, and arrived in the New World with his young wife Marie Charlotte (Carlota). They found Mexico idyllic at first, but liberal forces led by Juárez continued guerilla war. In 1867 Maximilian was obliged to surrender, and despite international pleas for clemency Juárez had him shot.

After the death of Maximilian Carlota stayed on in Europe, living in the Mirimar Palace, south of Trieste, until her death in 1927. The personal life of the young couple was not happy, but Lowry has nevertheless used their story as an emblem of tragic love.