Career
He is best known for having designed the national flag of Brittany. A former pupil of the Saint Martin"s day college of Rennes, Marchal went on to study architecture at the Rennes School of Artist In 1918 he joined the Breton Regionalist Union and became involved with its journal Breiz Atao ("Brittany Always!") and the nationalist youth movement Breton Youth.
In 1923 he designed the Breton national flag Gwenn ha du ("Black and White").
He also belonged to "Seiz Breur", a group of Breton artists. In constant conflict with the pro-Nazi nationalist Olier Mordrel, he finally broke with Breiz Atao.
At the 11 April 1931 congress, the PAB split. Mordrel set up the fascist Breton National Party, and Marchal joined the moderate Breton Federalist League, from which in 1932 he founded the journal Federal Brittany.
In 1934, he joined the Breton Federalist Movement, with Y. Gestalen, Francis Bayer of Kern, Goulven Mazéas and Rafig Tullou.
In 1938 he signed the manifesto of the Breton federalists, which affirmed:
The group is separate from the Gorsedd of Brittany. During the war, Marchal was not associated with the pro-Nazi activities of Mordrel and his followers. He left Brittany to live in Paris, where he worked installing gas.
He continued to contribute to some journals, such as Marius Lepage"s Le Symbolisme.
He died in poverty in 1963 in the commonroom of the Lariboisière hospital. A street of the district of Poultière in the North-East of Vitré has been named after him.
Morvan Marchal was buried in Paris in 1963 and re-buried in the family grave in Châteaugiron, near Rennes in Brittany on 24 January 1997.