Question: Manduessedum was a Roman fort in a province inhabited by Celtic Britons, Belgae, and what other people group?

Context paragraphs:
Manduessedum: Manduessedum or Manduesedum was a Roman fort and later a civilian small town in the Roman Province of Britannia.  Today it is known as Mancetter, located in the English county of Warwickshire.

Bewcastle Roman Fort: Bewcastle Roman Fort was a Roman fort, built to the north of Hadrian's Wall as an outpost fort and intended for scouting and intelligence.  The Roman name for the fort was Fanum Cocidi (as recorded in the Ravenna Cosmography), and means 'The Shrine of Cocidius', a deity worshipped in northern Britain.  The remains of the fort are situated at the village of Bewcastle, Cumbria, 7 mi to the north of the Roman fort at Birdoswald, on Hadrian's Wall.

British people: British people, or Britons, are the citizens of the United Kingdom, British Overseas Territories, and Crown dependencies.  British nationality law governs modern British citizenship and nationality, which can be acquired, for instance, by descent from British nationals.  When used in a historical context, "British" or "Britons" can refer to the Celtic Britons, the indigenous inhabitants of Great Britain and Brittany, whose surviving members are the modern Welsh people, Cornish people and Bretons.

Ot Danum people: Ot Danum (also known as Dohoi, Malahoi, Uud Danum or Uut Danum) people are the sub-ethnic of the Dayak people (hence also referred as Dayak Ot Danum) from the upper reaches of south Kapuas River, and along the Schwaner range, bordering West Kalimantan and Central Kalimantan, Indonesia.  They are the most important group of the upper Melawi River and culturally and linguistically the most distinct from the Malay people.  Besides, the Malay people, the Ot Danum people are also linguistically distinct from the Ngaju people who live along the middle reaches of Central Kalimantan's great rivers and who are numerically and linguistically the dominant Dayak people group in the area.  Just like most Dayak people group, majority of the Ot Danum people also practice Kaharingan religion.

Britannia: Britannia was a Roman-Britain province inhabited by the Celtic Britons, Belgae and Picts, encompassing parts of the island south of Caledonia (roughly Scotland) of the geographical region of Great Britain and is the name given to the female personification of the island.  It is a term still used to refer to the island.  The name is Latin, and derives from the Greek form "Prettanike" or "Brettaniai", which originally designated a collection of islands with individual names, including "Albion" or Great Britain.  By the 1st century BC, "Britannia" came to be used for Great Britain specifically.  The Romans had initially called the entire provincial island "Britain" and it was only when the island was split into four provinces that two were given the name "Britannia".  Although Britain had been designated part of the Roman Empire in 43 AD during the conquest of emperor Claudius it wasn't until the end of the 2nd century that Britannia had been pacified and fully adopted Roman practices.

Celtic Britons: The Britons, also known as Celtic Britons or Ancient Britons, were Celtic people who inhabited Great Britain from the British Iron Age into the Middle Ages, at which point their culture and language diverged.  They spoke the Common Brittonic language, the ancestor to the modern Brittonic languages.

King of the Britons: The title King of the Britons (Latin "Rex Britannorum") was used (often retrospectively) to refer to the most powerful ruler among the Celtic Britons, both before and after the period of Roman Britain up until the Norman conquest of England.  The Britons were the Brittonic-speaking peoples of what is now England, Wales, and southern Scotland, whose ethnic identity is today maintained by the Welsh, Cornish and Bretons.

Hen Ogledd: Yr Hen Ogledd (] ), in English the Old North, is the region of Northern England and the southern Scottish Lowlands inhabited by the Celtic Britons of sub-Roman Britain and the Early Middle Ages.  Its denizens spoke a variety of the Brittonic language known as Cumbric.  The Hen Ogledd was distinct from the parts of northern Britain inhabited by the Picts, Anglo-Saxons, and Scoti as well as from Wales, although the people of the Hen Ogledd were the same Brittonic stock as the Picts, Welsh and Cornish, and the region loomed large in Welsh literature and tradition for centuries after its kingdoms had disappeared.

Celtic mythology: Celtic mythology is the mythology of Celtic polytheism, the religion of the Iron Age Celts.  Like other Iron Age Europeans, the early Celts maintained a polytheistic mythology and religious structure.  Among Celts in close contact with Ancient Rome, such as the Gauls and Celtiberians, their mythology did not survive the Roman Empire, their subsequent conversion to Christianity, and the loss of their Celtic languages.  It is mostly through contemporary Roman and Christian sources that their mythology has been preserved.  The Celtic peoples who maintained either their political or linguistic identities (such as the Gaels in Ireland and Scotland, the Welsh in Wales, and the Celtic Britons of southern Great Britain and Brittany) left vestigial remnants of their ancestral mythologies, put into written form during the Middle Ages.

Ma'anyan people: Ma'anyan (colonial spelling Maanjan or Meanjan), Dayak Maanyak or Dayak Barito Timur people are a sub-ethnic group of the Dayak people indigenous to Borneo.  They are also considered as part of the east Barito Dusun group with the name Dusun Ma'anyan.  According to J. Mallinckrodt (1927), the Dusun people group is part of the Ot Danum people cluster, although later that theory was disproved by A. B. Hudson (1967), who argues that the Ma'anyan people are a branch of the Barito family.  The Ma'anyan people who are often referred to as Dayak people are also referred to as Dayak Ma'anyan.  The Dayak Ma'anyan people inhabit the east side of Central Kalimantan, especially in the East Barito Regency and parts of South Barito Regency which are grouped as Ma'anyan I.  The Dayak Ma'anyan people also inhabit the northern parts of South Kalimantan, especially in Tabalong Regency which refers to the Dayak Warukin people.  The Dayak Balangan people or Dusun Balangan people which are found in the Balangan Regency and the Dayak Samihim people that are found in the Kotabaru Regency are grouped together with the Dayak Ma'anyan people group.  The Dayak Ma'anyan people in South Kalimantan are grouped as Ma'anyan II.

Supporting paragraphs: Manduessedum Britannia
Answer: Picts