The Cohors I Morinorum was an infantry auxiliary unit of the Roman Empire army of the type cohors quinquagenaria peditata , whose existence is established from the last quarter of the 1st century to the beginning of the 5th century.
This auxiliary infantry unit contained a nominal five-hundred soldiers recruited from the Morini tribe, who inhabited the coastal region of Belgica province around the busy seaport of Gesoriacum (Boulogne, France). It was from the territories of this tribe that the Roman invasions of Britain conducted by both Caesar and Claudius had been initiated. Aside from military diplomata dating from the early-second century they are not evidenced by any epigraphy from Britain and are not mentioned in any literature or classical documentation until the Notitia Dignitatum, where they are listed as the late-fourth century garrison of the Ravenglass coastal fort in Cumbria.