Breton wasn't created, its a natural language. If you are asking about it's origins, it originated from Cornish, Celtic Brythonic language related to Welsh. A flux of Welsh/Cornish immigrants went to Armorica (western France now) in the Vth century. They mixed with local population and this region became a country called "Brittany". The language evolved on it's own. Cornish and Breton were still mutually understandable in the XIXth century. Breton language is still spoken by around 200,000 persons but this number decreases each year...
The Breton word for Brittany is "Bretagne." In the Breton language, it is often referred to as "Breizh." This term reflects the region's cultural and linguistic heritage, as Breton is a Celtic language spoken in Brittany.
Breton Party was created in 2002.
Breton Liberty was created in 1984.
Made in Cape Breton was created in 2002.
Breton Women at a Pardon was created in 1887.
Breton Education Centre was created in 1971.
Breton Liberation Front was created in 1963.
Breton Women at a Wall was created in 1892.
Transit Cape Breton was created in 1995.
Cape Breton Oilers was created in 1988.
Cape Breton University was created in 1951.
Breton Communist Party was created in 1971.