Breiz Atao (also Breizh Atao) (in Breton Brittany For Ever), was a Breton nationalist journal in the mid-twentieth century. It was written in french, and has always been considered as a french nationalist journal by the non-francized Bretons. The term is also used for the broader movement associated with the journal's political position.
Founded in 1918 in the aftermath of World War I, Breiz Atao would exist throughout the inter-war years. It was highly influenced by the Irish War of Independence, which began in 1916 and whose aftermath ran into the 1920s. Early on it adopted an official pan-Celtic policy, and a strong Pan-latin use of the french language. In its later years it became associated with a Nordicist blood and soil ideology with aspects in common with Nazism. It ceased publication in 1940, but was revived for an individual issue that appeared in 1944.