Possibly also known as Decangi, Deceangi, Cangi and Ceangi, the Deceangli had no real governement but they did have a tribal capital, Canovium, which late became the civitas capital
They were probably under military government like their welsh based neighbours, the Ordovices after the campaign of Agricola in 78AD. The extent of their tibal terrirories lay in the extreme northern coastal area of Wales; north west and north east Clwyd and northern Gwynedd.
Like the Ordovician, the Deceangli lived mainly in hillforts, notably in a series of settlements along the entire length of the Clwydian Range in the eastern part of their territory.
From Moel Hiraddug near the mouth of the Clwyd river, they are in a closesly formed chain along the eastern bank of the Moel y Gaer river. Continuing west along the northern Welsh coastline from the mouth of the Clwyd, are Deceanglian forts at Pen y Corddyn, Conwy Mountain at the mouth of the Conwy and Pen y Gaer further inland along the Conway valley, and Dinas Dinorwig overlooking the Menai Straits and Mona Insula.
'By the Icenian defeat all who were wavering between war and peace were reduced to quietude, and the army was led against the Ceangi (Deceangli). The country was devastated, booty collected everywhere, while the enemy declined to risk a battle, or, if he made a stealthy attempt to harrass the marching columns, found his treachery punished. And now Ostorius was within measurable distance of the sea which looks towards Ireland, when an outbreak of sedition among the Brigantes recalled a leader who was firm in his resolution to attempt new conquests only when he had secured the old.'
Canovium - (Caerhun, Gwynedd) - Cavalry fort on the Afon Conwy. The minor settlement outside the fort was possibly the civitas capital of the Deceangi.
Prestatyn - (Clwyd) - Fort and minor settlement.
Llandudno - (Gwynedd) - Roman copper mines on Great Orme's Head near Aberconwy. There was most certainly a settlement nearby.
Pentre - (Clwyd) - A small settlement serving the Lead/Silver Mines.
Ruthin - (Clwyd) - Fort at the head of the Vale of Clwyd, beside the Afon Clywedog.
Bryn y Gefeiliau (Gwynedd) - Fort on the Afon Llugwy between Betws-y-Coed and Capel Curig.