Carlisle, United Kingdom

By the early 2nd century, Carlisle was established as a prominent stronghold. The 'Stanegate' frontier, which consisted of Luguvalium and several other forts in a line east to Corbridge, was proving a more stable frontier against the Picts than those established deeper into Caledonia. In AD 122, the province was visited by Hadrian, who approved a plan to build a wall the length of the frontier. A new fort, Petriana, was therefore built in the Stanwix area of the city north of the river on Hadrian's Wall. It was the largest fort along the wall and was completed in stone by around AD 130. Like Luguvalium, which lay within sight, Petriana housed a nominal 1,000-strong cavalry regiment, the Ala Gallorum Petriana, the sole regiment of this size along the wall. Hadrian's successor Antoninus Pius abandoned the frontier and attempted to move further north; he built the Antonine Wall between the firths of Forth and Clyde. It was not a success and, after 20 years, the garrisons returned to Hadrian's Wall.

At one time, Carlisle broke off from Rome when Marcus Carausius assumed power over the territory. He was assassinated and suffered damnatio memoriae, but a surviving reference to him has been uncovered in Carlisle. Coins excavated in the area suggest that Romans remained in Carlisle until the reign of Emperor Valentinian II, from AD 375 to AD 392.

The period of late antiquity after Roman rule saw Cumbria organised as the native British kingdom of Rheged. It is likely that the kingdom took its name from a major stronghold within it; this has been suggested to have been broadly coterminous with the Civitas Carvetiorum, Carlisle. King Urien and his son and successor Owain became the subjects of a great deal of Arthurian legend. Their capital has been identified as the Cair Ligualid listed by Nennius among the 28 cities of Britain, which later developed into Caer-luel, whence the city's modern Welsh name Caerliwelydd. Rheged came under Northumbrian control before 730, probably by inheritance after Rienmelth, daughter of Royth and great-granddaughter of Urien, married Oswy, King of Northumbria. For the rest of the first millennium, Carlisle was an important stronghold contested by several entities who warred over the area, including the Brythonic Kingdom of Strathclyde and the Anglian kingdom of Northumbria. In 685, St Cuthbert, visiting the Queen of Northumbria in her sister's monastery at Carlisle, was taken to see the city walls and a marvellously constructed Roman fountain.

By the time of the Norman Conquest of England in 1066, Carlisle was in the possession of the Scots. It was not recorded in the 1086 Domesday Book. This changed in 1092, when William the Conqueror's son William Rufus invaded the region and incorporated Carlisle into England. The construction of Carlisle Castle began in 1093 on the site of the Roman fort, south of the River Eden. The castle was rebuilt in stone in 1112, with a keep and the city walls. The walls enclosed the city south of the castle and included three gates to the east, south, and north called the Irish or Caldew Gate, the English or Botcher Gate, and the Scotch or Ricker Gate respectively. The names of the gates exist in road names in Carlisle today. Carlisle Cathedral was founded as an Augustinian priory and became a cathedral in 1133. In 1157, Carlisle became the seat of the new county of Carliol (a name that was originally an abbreviation of Latin Carlioliensis, meaning "[Bishop] of Carlisle"); in 1177 the county was renamed Cumberland.

The conquest of Cumberland was the beginning of a war between Scotland and England which saw the region centred around Carlisle change hands a number of times. It was a major stronghold after the construction of the castle. During the wars, the livelihood of the people on the borders was devastated by armies from both sides. Even when the countries were not at war, tension remained high, and royal authority in one or the other kingdom was often weak. The uncertainty of existence meant that communities or peoples kindred to each other sought security through their own strength and cunning, and they improved their livelihoods at their enemies' expense. These peoples were known as the Border Reivers and Carlisle was the major city within their territories.