After Hadrian
In the years after Hadrian's death in 138, the new emperor, Antoninus Pius essentially abandoned the wall, leaving it occupied in a support role, and began building a new wall called the Antonine Wall, about 160 kilometres (99 mi) north, in what later became known as the Scottish Lowlands, though the short strip running West South West to East North East from coast to coast sometimes referred to as the Central Belt or Central Lowlands. This turf wall ran 40 Roman miles (about 37.8 mi (60.8 km)) and had significantly more forts than Hadrian's Wall. Antoninus was unable to conquer the northern tribes, so when Marcus Aurelius became emperor, he abandoned the Antonine Wall and reoccupied Hadrian's Wall as the main defensive barrier in 164. The wall remained occupied by Roman troops until their withdrawal from Britain.
In the late 4th century, barbarian invasions, economic decline, and military coups loosened the Empire's hold on Britain. By 410, the Roman administration and its legions were gone, and Britain was left to look to its own defences and government. The garrisons, by now probably made up mostly of local Britons who had nowhere else to go, probably lingered on in some form for generations. Archaeology is beginning to reveal that some parts of the wall remained occupied well into the 5th century. Enough also survived in the 8th century for spolia from it to find its way into the construction of Jarrow Priory, and for Bede to see and describe the wall thus in Historia Ecclesiastica 1.5, although he misidentified it as being built by Septimius Severus:
After many great and dangerous battles, he thought fit to divide that part of the island, which he had recovered from the other unconquered nations, not with a wall, as some imagine, but with a rampart. For a wall is made of stones, but a rampart, with which camps are fortified to repel the assaults of enemies, is made of sods, cut out of the earth, and raised above the ground all round like a wall, having in front of it the ditch whence the sods were taken, and strong stakes of wood fixed upon its top.
But in time the wall was abandoned and fell into ruin. Over the centuries the stone was reused in other local buildings.
The wall fascinated John Speed, who published a set of maps of England and Wales by county at the start of the 17th century. He described it as 'the Picts Wall' (or 'Pictes'; he uses both spellings). A map of Newecastle (sic), drawn in 1610 by William Matthew, described it as 'Severus' Wall', thus giving it the name ascribed by Bede. The maps for Cumberland and Northumberland not only show the wall as a major feature, but are ornamented with drawings of Roman finds, together with, in the case of the Cumberland map, a cartouche in which he sets out a description of the wall itself.
Read more about this topic: Hadrian's Wall