These were a mixed regiment of cavalry and infantry recruited from among the Delmatian tribes who occupied the area which is now modern Yugoslavia. Their presence is attested on an undated altarstone dedicated to the god Veterus from Carvoran in Northumberland which is probably from the third century. The unit is also recorded at the Carvoran fort in the Notitia Dignitatum of the late-fourth century. The military discharge certificate dated to AD105 may refer to Cohors IV Delmatarum.
