He was also a co-founder of the Movement for the Organization of Brittany (MOB) and leader of the Breton Liberation Front.
[3] In 1955 in Brest, Pierre Le Moine and other Breton nationalist founded the magazine Ar Vro and later Jeune Bretagne that became L'Avenir de la Bretagne; he was a regular contributor to Armor Magazine.
He was the president of the Menez Kamm, European Youth Center, opened in the property of Countess Vefa de Saint-Pierre.
He was the inspiration for the Blue Book of Brittany, which, without him, could not have been written or published, as recorded by Louis Mélennec.
He moved to Jersey in 1971 after his arrest alongside other Breton activists,[8] where he became President of the Société Jersiaise de Bienfaisance.