Abeozen was also a noted scholar of the Welsh language. Abeozen started contributing to the Breton literary journal Gwalarn in 1925. He worked as a teacher in Saint-Brieuc from 1927 to 1940 and founded the local branch of the communist Secours Rouge organization.
During the German occupation of France, he joined Roparz Hemon at the newly founded Radio Rennes Bretagne and wrote for Louisiana Bretagne, L"Heure Bretonne and Arvor.
As France was liberated Abeozen, like many Breton nationalists, was arrested for collaborating with the German occupants and spent fourteen months in prison.