Axel was the second of four children; he had two sisters, Hedvig Eleonora and Eva Sophie , and one brother, Fabian Reinhold. Two female cousins, Ulrika von Fersen and Christina Augusta von Fersen , were Swedish ladies-in-waiting and leading socialites of the Gustavian age.
Von Fersen's ancestors came from Estonia to Sweden at the time of the Thirty Years' War , which took place from to Von Fersen's father, the de facto parliamentary leader of the Hats party, was the most politically influential man in Sweden at that time and also one of the richest in the realm. His later education was primarily military. In October , he passed through Switzerland and in Ferney , he met the philosopher, Voltaire.
In January his travels took him to France where he paid court to the reigning monarch, Louis XV , and his mistress, Madame du Barry. While at Versailles he attended the ceremony of the Order of the Holy Spirit. A little over a week later, von Fersen met Marie-Antoinette , then Dauphine , for the first time:.
By the beginning of , von Fersen had returned to Sweden, where he remained for approximately three years, serving under his king, Gustavus III. In the late summer of , von Fersen traveled to Normandy with his friend, the Baron de Stedingk , to see a large army camp that was training under the command of the Duke of Broglie.
Besides military matters, they were treated to dinner and dances attended by the officers and their wives. Von Fersen later paid his respects to the French royal family for the first time since his grand tour more than three years earlier:.
