The mortarium kiln at Ellingham, excavated in 1976, contained an exceptional number of mortaria, including between thirty-seven and forty-nine individual mortaria stamped by Regalis, a potter known to have worked at Colchester; these factors indicate a production site of special interest. Large numbers of stamped and unstamped mortaria were incorporated into the structure of the kiln and these probably came from an earlier kiln on the same site or nearby. The mortaria are stamped by Regalis, by Lunaucis, with a herringbone stamp or with a trademark stamp. The potter Regalis appears to have moved from Colchester to work at Ellingham in the period AD 170–190, and the mortaria with stamps of Lunaucis and those with herringbone stamps also show strong links with the Colchester tradition. The potter using the trademark die belonged to quite a different tradition from the other three. Further work is needed to clarify the issue, but it is possible that this tradition came from West Stow in Suffolk, where a stamp of this rarely-recorded potter was found.