Olier Mordrel (29 April 1901 – 25 October 1985) is the Breton language version of Olivier Mordrelle, a Breton nationalist and wartime collaborator with the Third Reich who founded the separatist Breton National Party.
Before the war, he worked as an architect.
His architectural work was influenced by Art Deco and the International style of Le Corbusier.
He was also an essayist, short story writer, and translator.