Although the material was first recognised in stratified sequences at California, where it was used to date graves in a cemetery, the same fabrics are found across much of the Roman town. Indeed, because the sub-Roman fabrics were recognised relatively early on during Gil Burleigh's extensive excavations, it was possible to identify them on sites excavated later (Figure 4). Moreover, being alert to the existence of 5th-century (and later) activity in Baldock aided the interpretation of complexes of intercutting features and those that appeared on other grounds to be very late (such as the presence of clipped siliquae).
It is now clear that Ian Stead's assessment of the decline and end of Roman Baldock was placed much too early and that a number of his features could well date from the 5th century. Indeed, his concordance lists one feature (A112) whose date is assessed as 'IV→' (Stead and Rigby 1986, 418). It would be an interesting – but time-consuming – exercise to re-examine the ceramics from features assigned a 4th-century date (as well as others that are undated) to see how many contain the sub-Roman fabrics first recognised in 1983. Similarly, excavations carried out since 1994 (all funded through development control) have generally not had the intensive post-excavation analysis of pottery that Gil Burleigh was able to commission, so an examination of these archives could also well prove fruitful.
Similar material has also been found on sites outside Baldock. Only a kilometre to the north of the town, trial trenching at Blackhorse Farm in 1993-4 revealed a probable grubenhaus, which was associated with what was thought at the time of excavation to be Anglo-Saxon pottery of 5th- or 6th-century date (Fenton 1994, 16). Re-examination of the pottery shows that it falls into the sandy vegetable-tempered group known from sub-Roman sites in the town and is not comparable with early Saxon pottery from Bedfordshire or Cambridgeshire.
Further afield, the partial excavation of a late Roman farmstead during pipeline construction at Danes Field in Pirton (11km west of Baldock) revealed a sequence continuing until at least the end of the 4th century. An unworn coin of the House of Theodosius from a gully, Much Hadham 'Romano-Saxon' pottery (Ashworth Fabric 49) and sherds of thumb-impressed greyware in a sub-Roman fabric from a deep pit, and sub-Roman sherds in the final recut of a roadside ditch suggest that occupation certainly continued into the 5th century (Went and Burleigh 1990, 8). Although no features that could be dated later than the middle of the 5th century were located, two large conjoining rim and body sherds from a globular vessel resembling 6th-century Anglo-Saxon forms were found unstratified on a spoil heap close to the deep pit that produced 5th-century material; again, the fabric is sub-Roman, a variant of the dense sandy ware, reduced and very highly fired (Fitzpatrick-Matthews 2010, 141; Figure 5, 1).
A large heterogeneous collection of material was donated to North Hertfordshire Museums in 1990 from a garden at Springhead, Ashwell, about 10km north-north-east of Baldock. The site lies to the east of the springs forming the source of the River Rhee, a tributary of the Cam, and attest to almost continuous activity around the springs from at least the third millennium BC (Went and Colley 1990, 1). Seventeen sherds from three globular vessels in a highly micaceous fabric with grog, flint and quartz inclusions similar to Fabric 50 were identified, of which four adjoining sherds allowed a reconstruction of the profile of the upper half of a wide-mouthed sub-globular vessel of Myres's (1977, 7) Type I.1 with thumb impressions around the waist. Again, the material is closely related to sub-Roman fabrics but adapted to Anglo-Saxon forms; the date of this type is 6th century (Figure 5, 2).
A small shouldered and necked pot (Letchworth Museum Accession Number 1983.105) is said to have been excavated from a secondary burial in a burial mound at Pegsdon Heath (Beds) in 1892 by the local antiquary William Ransom (Rutherford Davis 1982, 140, no. 27; Figure 4, 3). A male inhumation burial 'in a slightly sitting posture' (presumably flexed at the knees or crouched) accompanied by an iron knife of 6th-century type was also recovered (Ransom 1886, 39), but it is not clear if this refers to the same burial. Nevertheless, the vessel is handmade and in a sandy fabric similar to Fabric 31; although stylistically a late 1st-century type, a sub-Roman date is possible on the basis of the fabric. However, Ransom also excavated a group of Romano-British burials nearby and it is possible that there has been some muddling of material, so that this vessel is of uncertain value to the material under discussion. The strangest of these vessels is a small handmade cup found in a garden at Gaping Lane, Hitchin, in 1939 (Figure 5, 4; Fitzpatrick-Matthews and Murray forthcoming).
It is similar in size and form to a number of Early Saxon globular cups with semi-circular handles published by Myres (1977), with a predominantly East Anglian distribution in the late 5th and early 6th centuries. The fabric and firing technique show greater similarity to Roman practice, though: the fabric is hard and highly micaceous, with abundant small sand, the oxidised surface showing flakes of mica (<1mm square), apparently added in a technique similar to mica dusting. The core of the vessel is a uniform reduced grey colour, visible at two points where what is assumed to have been a handle has broken off. The stump where this handle would have joined the lower body reveals a small central hole around 1mm in diameter, presumably the reason why the vessel has previously been surmised to have been a feeding bottle, which it cannot have been. At rim level, directly above the stump on the lower body, a break shows where the top of the handle would once have joined. Like the vessel from Dane Field, Pirton, this appears to be an 'Anglo-Saxon' form manufactured by a potter using Romano-British techniques.