Birdoswald
BANNA
On the 1922 map above the Fort is shown as Amboglanna.
The Name of the Fort
The problem of the Roman name of Birdoswald has been frequently discussed as a result of an apparent contradiction between the archeological evidence and the Notitia Dignitatum. In the Notitia the fort garrisoned by cohors I Aelia Dacorum is recorded as Amboglanna. This Dacian cohort is well attested at Birdoswald on a large number of insciptions .................. and consequently Birdoswald was identified as Amboglanna by Horsley. This was subsequently corrected by Haverfield (1918), to Camboglanna, which is how the name appears on the Rudge Cup and the Amiens patera (Heurgon 1951)
In 1821, an altar (RIB 1905) dedicated to Silvanus by the Venatores Bannieses was found inside the fort. This suggested that Banna a name that appears on the Rudge Cup, the Amiens patera and also in the Notitia was Birdoswald. Breeze and Dobson (1987, 272) have pointed out that, without the confusion engendered by the Notitia entry, the altar would have been quite sufficient to establish the identification of Birdoswald with Banna.
the solution was found by Hassall (1976, 113) in his discussion of the British section of the Notitia, where it is proposed that there is a lacuna in an earlier version of the document and with restoration of the text Camboglanna should thus be located at Castlesteads on the Cambeck, where cohors II Tungrorum is attested epigraphically (RIB 1981-3). This argument is decribed by Rivet and Smith (1979, 262) as "not only acceptable, but, once demonstated, obvious", and the identification has achieved general acceptance. (eg. Mann 1989, 75) The topographical relevance to Birdoswald of the name Banna, with its meaning of a spur or a promontory is very clear. *2