Blatobulgium Fort (Birrens)

Blatobulgium or Blatobvlgivm fort is a Roman Fort. The remains of this fort are quite impressive when approached from the south, where its southern defences, arranged along the edge of a natural scarp above the river are now covered in gorse bushes. The remains of stone-built buildings are visible across the whole of the interior, all beneath an overlying blanket of turf, except at the south-east corner, where several courses of stonework are visible; these belong not to the fort’s defences but to buildings in the retentura or rear of the camp, the corner-angle itself having been lost to erosion. The extensive ditch system and entrance causeway is especially prominent on the north, and a scatter of shaped stones on the west rampart marks the position of the gateway on this side.

Classical references for Blatobulgium Fort (Birrens)

The only classical reference for the name of the Birrens encampment is contained in the Antonine Itinerary of the late-second century. Iter II, “the route from the ‘Entrenchments’ to the port of Rutupiae, four-hundred and eighty-one thousand paces”, details the journey from Hadrian’s Wall to Richborough in Kent. In this itinerary the name Blato bulgio appears as the northern terminus, some 12 Roman miles from Castra Exploratorum (Netherby, Cumbria), both stations lying beyond the Wall of Hadrian.

The Blatobulgium Fort

A lead sling-shot was uncovered during excavations at Birrens within a layer tentatively dated to the mid-second century, which likely means that the auxiliary garrison were trained in the use of this weapon, possibly at the suspected training camp at Burnswark nearby.

The Dateable Pottery Evidence

Although there was plenty of pieces of South Gaulish decorated ware dateable to the Antonine period, there was absolutely no Flavian material.

The Blatobulgium Garrison

The second, and most frequently attested unit to be stationed at Birrens were the Second Cohort of Tungrians, a one-thousand strong part-mounted unit, originally recruited from amongst the Tungri tribe of Eastern Belgium. The name of this unit is recorded on no less than nine out of the twenty-four inscriptions so far recovered from the site.

This unit was probably in residence for a number of years, and, following losses due to battle or retirement, the garrison had to be bolstered by the addition of several small groups of Germanic tribesmen; many of whom brought their own peculiar deities to the Birrens fort.

The Second Cohort of Tungrians is also recorded on several altars at Castlesteads on Hadrian’s Wall, including at least one with the suffix Gordiana (RIB 1983), dated 241AD.

Other Deities Worshipped in Blatobulgium

Other Roman Military Sites in the Area

There are several temporary camps in the neighbourhood of the Blatobulgium fort; 4 around Birrens itself (NY2174), 2 more at Middlebie nearby (NY2076) and a further 2 at Kirkpatrick-Fleming (NY2870) a short way along the road to the south-east. There is also a Roman fortlet and 2 practice works at Burnswark a little distance along the road to the north-west.

References for Blatobvlgivm

• Chronicle of the Roman Emperors by Chris Scarre (Thames & Hudson, London, 1995);
• The Roman Occupations of Scotland by B.R. Hartley in Britannia iii (1972) pp.1-55;
• The Roman Inscriptions of Britain by R.G. Collingwood and R.P. Wright (Oxford 1965);

Map References for Blatobvlgivm

NGRef: NY2175 OSMap: LR85

Roman Roads near Blatobvlgivm

NW (9) to Ladyward (Dumfries & Galloway) Iter II: ENE (15) to Castra Exploratorvm (Netherby, Cumbria) Military Road: SE (17) to Uxelodvnvm (Stanwix, Cumbria) Military Road: NW (3) to Bvrnswark Probable road: ESE (4) to Kirkpatrick N (19) to Raebvrnfoot