Louis I, Grand Duke of Hesse
In 1776, he became engaged to Sophie Dorothea of Württemberg, eldest daughter of Frederick II Eugene, Duke of Württemberg. The engagement was broken off so that Sophia Dorothea could marry Louis's recently widowed brother-in-law Tsarevich Paul Petrovich, son and heir of Catherine II "the Great", Empress of Russia. He received a monetary compensation when the engagement was broken.
Maria Feodorovna (Sophie Dorothea of Württemberg)
The close relationship between Paul and Catherine Nelidova, one of Maria's ladies-in-waiting, was the cause of the first crack in their marriage. Paul's liaison, a deeply intense but, according to him, only platonic attachment to Nelidova, was particularly painful for Maria, as the other woman had been her friend. Her relations with Nelidova became very bitter for several years. Later, however, she began to accept Paul's word that it was only a friendship, and eventually Maria not only reconciled with the idea, but joined forces with Nelidova in an attempt to moderate Paul's increasingly neurotic temperament.