Poutrocoet was an early medieval pagus

Pagus

In the later Western Roman Empire, following the reorganization of Diocletian, a pagus became the smallest administrative district of a province....

in Brittany

Brittany

Brittany is a cultural and administrative region in the north-west of France. Previously a kingdom and then a duchy, Brittany was united to the Kingdom of France in 1532 as a province. Brittany has also been referred to as Less, Lesser or Little Britain...

. The term "Poutrocoet" is Breton

Breton language

Breton is a Celtic language spoken in Brittany , France. Breton is a Brythonic language, descended from the Celtic British language brought from Great Britain to Armorica by migrating Britons during the Early Middle Ages. Like the other Brythonic languages, Welsh and Cornish, it is classified as...

, and contemporaries translated it literally into Latin

Medieval Latin

Medieval Latin was the form of Latin used in the Middle Ages, primarily as a medium of scholarly exchange and as the liturgical language of the medieval Roman Catholic Church, but also as a language of science, literature, law, and administration. Despite the clerical origin of many of its authors,...

 as pagus trans silvam, the "country beyond the forest", as in certain charters in the cartulary of Redon Abbey

Redon Abbey

Redon Abbey, or Abbey of Saint-Sauveur, Redon , in Redon in the present Ille-et-Vilaine, Brittany, France, is a former Benedictine abbey founded in 832 by Saint Conwoïon, at the point where the Oust flows into the Vilaine, on the border between Neustria and Brittany.-History:In 832 Ratwili, a local...

. Originally a part of Domnonée, it was much larger than the other pagi, and was perhaps just "a vast region that had escaped the primitive division into pagi". sparsely populated and heavily forested. It evolved into the region of Porhoët

Porhoët

The first recognised vicomte de Porohoet was Guithenoc , formerly of Guilliers. Guithenoc was born in Guilliers, Moribihan, Brittany, Western France. He married Allurum of Guilliers. He became Vicomte, and in about 1008 he moved to La Trinite, in Porhoet, Morbihan, Brittany. There he built...

, which, by circa 1000, was a viscounty.

Poutrocoet was also a diocese

Diocese

A diocese is the district or see under the supervision of a bishop. It is divided into parishes.An archdiocese is more significant than a diocese. An archdiocese is presided over by an archbishop whose see may have or had importance due to size or historical significance...

 for a time. Until the 860s the Bishops whose seat was Aleth

Ancient Diocese of Saint-Malo

The former Breton and French Catholic diocese of Saint-Malo existed from at least the seventh century until the French Revolution. Its see was at Aleth, to a point in the twelfth century, when it moved to Saint-Malo. Its territory extended over some of the modern departments of Ille-et-Vilaine,...

 usually titled themselves episcopus in Poutrocoet or episcopus in pago trans silvam, sometimes episcopus in Aleta civitate (bishop in the 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...

of Aleth"). In the 860s they began to be styled "Bishops of the see of Saint Malo" (episcopus super episcopatum sancti Machutis).