The Osismii were a Gaulish tribe on the western Armorica

Armorica

Armorica or Aremorica is the name given in ancient times to the part of Gaul that includes the Brittany peninsula and the territory between the Seine and Loire rivers, extending inland to an indeterminate point and down the Atlantic coast...

n peninsula. They were first described as the Ostimioi by the Greek

Ancient Greece

Ancient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...

 geographer and traveller Pytheas

Pytheas

Pytheas of Massalia or Massilia , was a Greek geographer and explorer from the Greek colony, Massalia . He made a voyage of exploration to northwestern Europe at about 325 BC. He travelled around and visited a considerable part of Great Britain...

 in the fourth century BC. He situated them at the end of the peninsula of Kabaïon, which is not identifiable today. Their name (Ostimioi) means "the farthest" or "those at the end of the world". Their territory corresponded broadly to the modern French département of Finistère

Finistère

Finistère is a département of France, in the extreme west of Brittany.-History:The name Finistère derives from the Latin Finis Terræ, meaning end of the earth, and may be compared with Land's End on the opposite side of the English Channel...

, whose name reflects the same meaning in Latin Finis Terræ, i.e. end of the earth. Their chief city was Vorgium, modern Carhaix.

They survived into Roman times and are found in the texts of Julius Caesar

Julius Caesar

Gaius Julius Caesar was a Roman general and statesman and a distinguished writer of Latin prose. He played a critical role in the gradual transformation of the Roman Republic into the Roman Empire....

, Pliny the Elder

Pliny the Elder

Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...

, and Strabo

Strabo

Strabo, also written Strabon was a Greek historian, geographer and philosopher.-Life:Strabo was born to an affluent family from Amaseia in Pontus , a city which he said was situated the approximate equivalent of 75 km from the Black Sea...

. They submitted to Caesar during the Gallic Wars

Gallic Wars

The Gallic Wars were a series of military campaigns waged by the Roman proconsul Julius Caesar against several Gallic tribes. They lasted from 58 BC to 51 BC. The Gallic Wars culminated in the decisive Battle of Alesia in 52 BC, in which a complete Roman victory resulted in the expansion of the...

, in 57 BC. The next year, they revolted along with the Veneti

Veneti (Gaul)

The Veneti were a seafaring Celtic people who lived in the Brittany peninsula , which in Roman times formed part of an area called Armorica...

, but were put down. They became a Roman civitas

Civitas

In the history of Rome, the Latin term civitas , according to Cicero in the time of the late Roman Republic, was the social body of the cives, or citizens, united by law . It is the law that binds them together, giving them responsibilities on the one hand and rights of citizenship on the other...

and their identity survived into Late Antiquity

Late Antiquity

Late Antiquity is a periodization used by historians to describe the time of transition from Classical Antiquity to the Middle Ages, in both mainland Europe and the Mediterranean world. Precise boundaries for the period are a matter of debate, but noted historian of the period Peter Brown proposed...

, but their Romanisation wore off.

Sources

• Smith, Julia M. H. Province and Empire: Brittany and the Carolingians. Cambridge: Cambridge University Press, 1992.