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.
Sophia Dorothea of Hanover
Sophia Dorothea married her cousin, Crown Prince Frederick William of Prussia, heir apparent to the Prussian throne, on 28 November 1706. They had met as children when Frederick William had spent some time in Hanover under the care of their grandmother, Sophia of Hanover, and though Sophia Dorothea disliked him, Frederick William had reportedly felt an attraction to her early on.