Louis Napoléon Le Roux (29 May 1890 – 5 August 1944) was a Breton nationalist. He is also known as Loeiz-Napoleon Ar Rouz in the Breton language. In 1911 he was one of the founders of the Breton Nationalist Party with Camille Le Mercier d'Erm. He typically signed himself Louis N. Le Roux, perhaps in order to avoid using the name 'Louis Napoléon'.He contributed to the bulletin Brug (heather) published by Émile Masson from Pontivy, between 1913 and 1914, which promoted socialist and radical ideas to the peasantry of Lower Brittany. Having exiled himself to Switzerland to avoid fighting for France in World War I, he left for Ireland, where he established good relations with nationalist leaders.