Louis Frederick John Spencer, Viscount Althorp (born 14 March 1994), is a British aristocrat who is a member of the Spencer family. He is the fourth child and eldest son of Charles Spencer, 9th Earl Spencer, and his first wife, Victoria Lockwood. Nephew of Diana, Princess of Wales, and first cousin to Prince William and Prince Harry, he is the heir apparent to the earldom of Spencer.
Louis has 2 sisters and one brother.