During the 5th century (or earlier, if Guy Halsall (2012, 213) is correct), Saxon settlement began and there were inevitably contacts between incomers and the indigenous Britons. There are, for instance, structures resembling grubenhäuser in Baldock, including at least one 4th-century example (although this may actually be a different type of late Roman sunken-featured building (Tipper 2004, 7). The structure at Blackhorse Farm (Fenton 1994, 16; Phillips and Duncan 2009, 159) was a more definite grubenhaus, although as seen above, the pottery associated with it was of sub-Roman rather than Anglo-Saxon type. Similarly, the 6th-century jars from Ashwell (Went and Colley 1990, 16) were manufactured in a sub-Roman fabric.
While it may be possible to argue for a continuity of clay and temper sources rather than a continuity of production, the similarities in firing techniques indicate a continuity of tradition. In other words, the people producing the sub-Roman pottery in the 5th century were the ancestors of those producing Anglo-Saxon pottery a few generations later. This suggests that interactions with Anglo-Saxon settlers were not as violent as is often assumed. Indeed, the process of change in the Baldock area seems to have been one that involved a shift from a Roman style of consumable identity to an Anglo-Saxon.