Background
Louis was born at Philippsthal as the son of Landgrave William and his wife Ulrika Eleonora of Hesse-Philippsthal-Barchfeld.
Louis was born at Philippsthal as the son of Landgrave William and his wife Ulrika Eleonora of Hesse-Philippsthal-Barchfeld.
He fought for the Kingdom of Naples (later Kingdom of the Two Sicilies). From 1813 until his death, he was the ruling Landgrave of Hesse-Philippsthal. A prince of the family of the Landgraves of Hesse-Philippsthal, he fought for the Kingdom of Naples during the Napoleonic Wars.
In the course of the War of the Third Coalition, he commanded the garrison of the fortress of Gaeta in the siege laid by the French in 1806, refusing to obey the order of the Neapolitan government to surrender lieutenant
His troops resisted for six months, until 18 July after Louis, while leading his men on the bastions, was wounded on 10 July and had to leave the fortress. Later, together with colonel Nunziante and lieutenant colonel Bardot, an expedition of 4,000 men who, in 1807, left Sicily to attempt the reconquest of the mainland of Naples.
They were however defeated in the Battle of Mileto of 28 May 1807.