"Your Highness, with respect, you can keep your landly titles, for the sea is my Demense."
— John de Luxembourg, when offered a lordship by Philip III
John of Luxembourg (Jean de Luxembourg) was a Burgundian sailor and admiral in the early and mid fifteenth century, and considered the driving force behind the expansion and advancement of the Burgundian Navy.
Born sometime in 1400 as the illegitimate son of Waleran III of Luxembourg, Count of Ligny, not much is known about his early life before 1413.
Discontent with his treatment at home, Jean joined the Burgundian Navy in 1413. At the time, the Burgundian Navy was a small collection of cogs and carracks, but several ships had been outfitted with experimental cannons. The first three years of his service were unremarkable, as he slowly rose in the ranks, but in 1416 the First War of the Lions broke out between Bohemia and Brandenburg. The Hollandic Crown, consisting of the Counties of Holland, Zeeland, and Hainaut, sided with Bohemia against the alliance of Burgundy, Brandenburg, and France.
Holland initially attempted to establish a blockade of Burgundys ports in Flanders, to which Hollands better established navy was better handled for. Tasked with preventing that, the Burgundian Navy engaged the Hollanders as they were attempting to blockade the city of Ostend. After initial botches by the commanding admiral of the Burgundian ships, the commanders death in combat opened a void in the chain of command. As confusion began to fill the Burgundian formation, Jean de Luxembourg took personal command and reversed their fortunes, routing the Hollander fleet.
After the victory at Ostend, de Luxembourg lead the naval portion of Burgundys counterattack. In light of the collapse of the Hollander forces after the battle of Rotterdam, and the Hollandic Crowns annexation into Burgundy, he was made Admiral of the Netherlands, the title for the overall commander of Burgundys naval forces, at the age of 21.