He was the first husband of Joséphine Tascher de La Pagerie, who later married Napoleon Bonaparte and became empress of France.

[1] He served in the American Revolutionary War under the Count of Rochambeau, and became acquainted with the court of King Louis XVI upon his return to France.

[1] A supporter of the French Revolution, Beauharnais was elected a deputy of the nobility to the Estates-General of 1789, where he was one of the first nobles to go over to the Third Estate, and voted in favor of the abolition of feudalism.

Accused of having poorly defended Mainz during the siege in 1793, and considered an aristocratic suspect, he was jailed in Carmes Prison and sentenced to death during the Reign of Terror.

Alexandre was the third of three sons born to him by his first wife Marie Henriette Pyvart de Chastullé (1722–1767) - the first died in infancy, and the second was Francis VI of Beauharnais.