In another article 'Early medieval army sizes', I reviewed the limited evidence on the size of early medieval armies and came to the conclusion that they appear to have been quite small, numbered in scores or perhaps hundreds.
Small-scale armies might be expected to engage in small-scale warfare, such as internal quarrels or border raids and skirmishes not too far from home. What do we know about the campaigning range of early medieval armies?
The following battles are mentioned in either Bede or Annales Cambriae between 550 and 700, for which a location and/or the participants can be identified or inferred.
Date: 573 (Annales Cambriae)
Known participants: Gwenddoleu son of Ceidio (territory unknown); Peredur and Gurci (territory possibly York, as discussed in another article 'Peredur')
Location: Uncertain, traditionally placed at Arthuret House near Longtown in Cumbria (see article 'The Battle of Arthuret' for evidence and discussion)
Date: 603 (Bede Book I Ch. 34)
Known participants: Aethelferth of Bernica; Aidan mac Gabran of Dal Riada (Bede Book I Ch. 34)
Location: Unknown; however the territories of Bernicia and Dal Riada are a long way apart (see sketch map). If Gododdin had been absorbed into Bernicia by then (unknown), Bernicia and Dal Riada might have shared a border, depending on the territory occupied by Strathclyde (called Alt Clut at the time).
Date: 613 (Annales Cambriae; see article 'Dating the Battle of Chester' for discussion)
Known participants: Aethelferth of Bernicia (Bede, Book II Ch 2); Selyf ap Cynan of Powys (Annales Cambriae)
Date: 617 (Bede Book II Ch. 12)
Known participants: Aethelferth of Bernicia; Eadwine of Deira; Raedwald of the East Angles and his son Raegenhere (Bede Book II Ch. 12)
Location: Probably Bawtry, since the River Idle flows north-south there and hence has an east bank
Date: 627 (Bede Book II Ch. 9)
Known participants: Eadwine of Deira/Northumbria; Cuichelm of the West Saxons (Bede Book II Ch. 9)
Location: Unknown*; however, the territories of Northumbria and the West Saxons are separated by a couple of hundred miles
Date: 12 October 633 (Bede Book II Ch. 20)
Known participants: Eadwine of Deira/Northumbria; Penda of Mercia; Cadwallon of Gwynedd (Bede Book II Ch. 20)
Location: Usually located at Hatfield Chase near Doncaster
Date: 634 (Bede Book III Ch. 1-2)
Known participants: Oswald of Bernicia/Northumbria; Cadwallon of Gwynedd (Bede Book III Ch. 1)
Location: Near Hexham (Bede Book III Ch. 2)
Date: 5 August 642 (Bede Book III Ch.9)
Known participants: Oswald of Bernicia/Northumbria; Penda of Mercia (Bede Book III Ch.9)
Location: Unknown. Traditionally located at Oswestry on the basis of the place name ("Oswald's Tree"), though this is not certain.
Date: 635 (Bede Book III Ch. 18)
Known participants: Penda of Mercia, Sigebert and Egric of the East Angles
Location: Unknown. East Anglia and Mercia may well have shared a border by then (depending on the position of the Middle Angles, who occupied a territory between Mercia and East Anglia and who were a sub-kingdom of Mercia in the 650s)
Date: 15 November 655 (Bede Book III Ch. 24)
Known participants: Oswy of Bernicia/Northumbria; Penda of Mercia (Bede Book III Ch. 24)
Location: Near Leeds. Penda had campaigned as far as Bebbanburgh in Northumbria some time earlier, as Bede mentions this casually as the background to a miracle story (Bede Book III Ch. 16).
Date: 679 (Bede Book IV Ch. 21)
Known participants: Ecgfrith of Northumbria and his brother Aelfwine; Aethelwald of Mercia (Bede Book IV Ch. 21)
Location: Near the River Trent (Bede Book IV Ch. 21).
Date: 20 May 685 (Bede Book IV Ch. 26)
Known participants: Ecgfrith of Northumbria; Bridei king of the Picts (Bede Book IV Ch. 21; the name of the king of the Picts is given in Historia Brittonum Ch. 57)
Location: In Pictish territory. The exact location is uncertain; the two leading candidates are Dunnichen in Angus and Dunachton in Badenoch (see Wikipedia)
Three of the battles in the list were fought at unknown locations (Degsastan, the battle between Northumbria and the West Saxons, the battle between the East Angles and Mercia). The battle between the East Angles and Mercia may have been fought between neighbouring kingdoms with a shared border. If we take the heartland of the kingdom of East Anglia to be King Raedwald's home near modern Rendlesham in Suffolk, and the heartland of the kingdom of Mercia to be modern Tamworth, they are separated by about 120 miles as the crow flies. If the battle was fought near the halfway point - its location is not recorded - each army would have had to travel about 60 miles. This is a non-trivial distance to walk, or even to ride on horseback, but it isn't vast. Bernicia and Dal Riada are separated by a similar distance. Northumbria and the West Saxon kingdoms are further apart - York to Winchester is about 200 miles, Bamburgh to Winchester is over 300 miles - so we can reasonably infer that at least one army had travelled a considerable distance from their home territory.
The battle of the Trent and the battle of Winwaed were fought between Mercia and Northumbria, who may have been neighbouring territories by then (depending on what had happened to the kingdoms that previously occupied the Leeds and North Midlands areas). Northumbria had more or less united Bernicia and Deira by the time of these two battles and so had become quite a large territory, extending from at least Bamburgh in the north to at least the York area in the south, a distance of around 130 miles or so. While warriors from the York area would not have had to travel far to a battle in Leeds (only twenty miles or so) or along the northern stretch of the Trent, any component of the army that had started from Bamburgh would have covered well over a hundred miles, and possibly anything up to two hundred miles from Bamburgh to the middle or upper Trent. From Mercia, the upper and middle Trent is very close at hand, only a few dozen miles from Tamworth, but Leeds or the northern Trent is more like 60 to 90 miles.
Maserfelth may also have been fought on or near a shared border, depending on its location. If Maserfelth was Oswestry, then Oswald of Northumbria was anything up to 200 miles from home. If it was in the Makerfield area near Wigan it may have been in a border zone between Mercia and Northumbria, although it would still have been 150 miles or so from Bamburgh and something like 90 miles from Tamworth.
If Arderydd/Arthuret was fought at its traditional location near Longtown in Cumbria, and if Peredur's traditional association with York is correct (two 'ifs'), then Peredur was about 100 miles from home at the battle.
At Caerlegion/Chester, Selyf of Powys may have been on his home ground if Chester was part of the territory of Powys, and in any case had not had to travel far. Aethelferth of Bernicia, however, was nearly 200 miles from the heartland of his territory at Bebbanburgh (modern Bamburgh).
At the battle on the east bank of the Idle, Raedwald of the East Angles was about 130 miles from his heartland at Rendlesham in what is now Suffolk, and Aethelferth was 160 miles from Bebbanburgh. Eadwine of Deira was in exile at Raedwald's court at the time, so may have travelled to the battle with Raedwald.
At Haethfelth, Cadwallon of Gwynedd was about 140 miles from his territory (taking Degannwy, near Conwy, as the heartland of Gwynedd; the distance is greater if you take Anglesey as the core of Gwynedd).
At Hefenfelth, Cadwallon of Gwynedd was around 200 miles from his territory, and had been in Northumbria for a year according to Bede (Book III Ch. 1). Oswald of Northumbria had been in exile on Iona and had presumably travelled from there, also about 200 miles, to reclaim his patrimony.
Either of the leading candidate locations for Nechtansmere is a long way from home for Ecgfrith of Northumbria; both are about 150 miles from Bamburgh (travelling by land via Stirling).
So, of the twelve battles in the list, we can say with reasonable certainty that in five of them (Caerlegion, the Idle, Haethfelth, Hefenfelth and Nechtansmere) at least one of the participating forces had had to travel 130 to 200 miles from the heartland of its territory to the battle site. This does not necessarily imply that every member of the army had travelled the full distance, as the distance from the closest region of the relevant kingdom could be a good deal less than the distance from its nominal heartland, and an army might operate in allied or subject territories beyond its own borders.
The battles in the list are most unlikely to be a representative sample. They are those which at least one chronicler thought worth recording and that have come down to us, so they probably represent battles that were considered especially significant or noteworthy at the time. Bede's casual reference to Penda's otherwise unrecorded campaign in Northumbria, mentioned in passing as the background to a miracle story, indicates that not all warfare was recorded. Long-distance campaigns may have been particularly worthy of note and thus especially likely to be recorded, in which case this would be a very biased sample. (Not that we are likely to get a better one).
Nevertheless, it does demonstrate that at least some early medieval kingdoms could field an army a considerable distance from their core territories, and in the case of Cadwallon of Gwynedd and his campaign against Northumbria, could do so for an extended time (over a year). It is not possible to say whether this was commonplace, unusual or exceptional, but it was clearly possible.
Sketch map showing the approximate locations of the various kingdoms here.
Annales Cambriae, available online
Bede, Ecclesiastical history of the English people. Translated by Leo Sherley-Price. Penguin Classics, 1968, ISBN 0-14-044565-X.
Historia Brittonum, available online
Annals of Ulster, available online
*There's a legend that the battle took place in Derbyshire, but as this location
depends on a pun in modern English, I have severe doubts as to its veracity.