Skip to content

Divide et Impera — Another Way to Look at Hadrian’s Wall

Maybe a better way to understand Hadrian’s Wall is to look at it as a dividing line splitting Britain exactly in half on a line from north to south (Haltwhistle is popularly ascribed as the centrepoint of Great Britain).

The Roman surveyors were able not only to pick this point, but at the same time, site the Wall along the narrowest isthmus in England, between the Tyne and the Solway — thus the Wall sits in an absolutely plum place on the island. Not only this, but further north in Caledonia they were able to pick the narrowest isthmus in all of Britain (barring the Northwest Highlands) between the Forth and the Clyde, to build their second frontier 20 years later.

The Wall is generally understood to be a multi-purpose construction. All great infrastructure really is. These functions were:

  1. To defend the Empire from barbarian tribes.
  2. To provide a tangible limit to the Empire.
  3. To monitor enemy barbarians to the north.
  4. To attack enemy barbarians to the north.
  5. To regulate trade across the boundary.
  6. To regulate movement across the boundary.
  7. To make a symbolic statement and project Rome’s might.

Whenever the Romans were faced with a political challenge or a new territory, they employed a fundamental strategy from the getgo: divide and rule, with its equally ancient corollary being: my enemy’s enemy is my friend. (In a later age, the British Empire employed the same formula and doctrine, particularly in India).

The Romans and in particular, Caesar, would go into a new place and immediately befriend the weakest tribe and whomever else was willing to form an alliance. This would usually create a division of loyalties in the region, which is what the Romans wanted. They would then proceed to attack the strongest of their enemies, one by one until every tribe had been toppled or surrendered and thus forced under the protection of the Roman People. They knew that if all of the foreign tribes were allowed to unite in confederacy against the common enemy of Rome, they would be much harder to beat. So they purposely engineered divisions among populations of foreign countries like Gaul in order to keep them weak and in a state of perpetual distrust with one another.

The easiest way for Emperor Hadrian to combat the perennially wild and rebellious, but deeply mysterious and coveted island of Britannia, was to to split the relatively civilised southern half from the volatile northern section. That is not to say Caledonia was beyond Rome’s sway, or impossible to defeat, but that it was a tougher prospect that needed dealing with separately and thus needed further subdividing within it. This further subdivision in Caledonia was done by way of the Antonine Wall, and 70 years prior to that, by the Gask Ridge string of forts along the Highland Line.

The Gask Ridge, 84 AD

Later on in the occupation there were further subdivisions in southern Britain, primarily between Britannia Inferior (Lower Britain governed from York) and Britannia Superior (Upper Britain governed from London) during the rule of Severus, although this division was done to limit the power of any single governor in the province, who may have presented a threat to the Emperor.

We can also see this approach in the subdivision of Northumbria. That is, the land between the two walls (which much later became the sub-province of Valentia).

The Devil’s Causeway was a road and grain route pre-dating the construction of Hadrian’s Wall. This formed a geo-political division orthogonal to the Stanegate, the east-west road that also preceded the Wall.

Map of Devil's Causeway

Sections of the Devil’s Causeway still form part of the A697 today, parallel to the A1. The road started at Corbridge, branching north-east off Dere Street — which originated with the legendary commander, Agricola (Governor 77-84 AD) and formed his main route into Caledonia.

Agricola – from

The Devil’s Causeway terminated at the port of Berwick, splitting modern Northumberland in half. This separated the more peaceful settled tribes in the east and south, from Tynemouth and the other maritime strongholds, along with their neighbouring farmlands, from the wilder hillier, perhaps Pictish, herder tribes in the north and west beyond Rothbury.

Altogether five key dividing lines in northern Britannia were:

  • Stanegate (77 AD)
  • Devil’s Causeway (77 AD)
  • Gask Ridge (84 AD)
  • Hadrian’s Wall (122 AD)
  • Antonine Wall (142 AD)

Rather than purely defensive fortifications, these should also be thought of as foreign policy instruments used to undermine and disrupt existing tribal political networks and power structures in the territories that were most challenging to Rome.

Read more on this subject in relation to the importance of Tynemouth to the Romans in this post here:


Leave a Reply

Your email address will not be published. Required fields are marked *