Background
William was born at Bückeburg, Schaumburg-Lippe, seventh child and third son of George William, Prince of Schaumburg-Lippe (1784–1860), (son of Philip II, Count of Schaumburg-Lippe and Landgravine Juliane of Hesse-Philippsthal) and his wife, Princess Ida of Waldeck and Pyrmont (1796–1869), (daughter of George I, Prince of Waldeck and Pyrmont and Princess Augusta of Schwarzburg-Sondershausen).