We do not have to assume the large-scale removal
of garrison limitanei (lightly armed border units in Late
Roman armies which were used to pin down attackers until more
heavily-armed reinforcements could arrive). The new work on coastal
defences and the fact that the barbarians stopped at the Wall
suggests that for the moment the frontiers had held.
In relation to this, the mention by Gildas of
the provision of exemplaria armorum makes it clear that
the Britons were being instructed on the local manufacture of
equipment which up to now had normally been supplied by the state
ordnance factories, especially those in the Danubian provinces.
If what Gildas describes as the legio being
withdrawn when the second Pictish war took place was indeed the same
force that had been sent by Theodosius the Great to deal with the
first Pictish war in 389 or 390, then it may have been in Britain
much longer than was intended. There is a minor problem with this
in that with the exact form described in the Notitia Dignitatum
(a list of dignitaries and their areas of responsibility in the Late
Roman empire at about AD 395), the force must date from 395 or later,
since it includes a unit named after Honorius (equites Honoriani
However, the possibility must be allowed that this
unit was a later addition or the result of a reorganisation of an
existing force. If it was, then a taskforce becoming almost a fixture
provides one possible answer for that presence of a comes
Britanniarum in the Notitia Dignitatum over which much ink
has been spilt. The Notitia army, nine units of comitatenses,
looks just like a taskforce.
If there was, therefore, a campaign in 398 (following
the defeat of Gildo) by the Romans against barbarians who were threatening
Britain, it is likely it was a sudden decision to seize an unforeseen
opportunity once forces had been freed up in Africa.
Stilicho may have harboured long term ambitions for
a major offensive in Britain, but the moment was generally inauspicious.
A withdrawal of as many troops as possible in 399, which was intended
to be temporary, seems likely, coupled with a further reorganisation
of the coastal command. Such a policy is especially convincing if an
unexpected success had sapped barbarian confidence. Even so, Stilicho's
withdrawals may not have been as drastic as has often been thought, even
though he had to prepare to deal with Alaric and his Goths, who were
always a major thorn in his side.
So by the start of the fifth century, the scene in
Britain was one of steadily declining professional troop numbers
combined with a probable increase in the hiring and settling of
barbarian laeti to make up the difference. The same practise
was standard in Gaul, where it is better attested and was practised
for a much longer period of time.
These laeti, mostly Saxons it seems, have
left grave goods and pottery behind them where they settled and died,
usually in settlements that were located immediately outside the
fortified walls of the remaining Roman cities.
Despite an apparently stable picture in Britain,
the troubles that had been inflicted upon the empire had clearly
taken their toll, and were continuing to do so. The official import
into Britain of new coinage in large quantities came to an end in 402,
although it was still being produced internally in much smaller
Final nail in the coffin
In 405 more troops were withdrawn from Britain to
form part of the Roman army that defeated the Goths in northern Italy.
In fact, Stilicho's attention for much of his period in office seemed
to have been spent trying to outmanoeuvre Alaric and his Goths, or at
least limit their scope for any successes against 'his' empire. In the
end he lost his battle, assassinated by an opposing faction from within
the imperial court itself. The Late Roman administration was often its
own worst enemy.
The British provinces themselves were relatively
isolated by 406. Their landowning classes had not taken part in the
trend that was popular on the Continent, where the nobility were
becoming deeply involved in imperial administration. The British
aristocracy also greatly feared an invasion from across the Channel
by those barbarians that were now crossing the Rhine and invading
They constantly lacked support from the empire in
their fight against barbarian incursions, so from 406 the remaining
soldiers, always the source of such support, raised a series of their
own claimants to the throne. Initially this was both for the throne
of Britain and the empire but, after 409, British ambitions were
An early Saxon brooch was was discovered in modern England
View the Roman invasion and conquest in a series
of detailed maps.
The timing is uncertain, but almost at the same
time as a wave of barbarians crossed the Rhine on the last day of
406, Stilicho detached the British diocese from the western imperial
government. What followed from these two events was to prove fatal
for Britain as part of the Roman world.
There was already some sign that the situation in
Britain was tense. Irish raiders were attacking the south coast,
although Stilicho's defensive arrangements seem to have accurately
assessed this probability. However, the Gothic Wars of 402-403 and
404-405 already meant that imperial troops were concentrated on Italy,
so Gaul and Britain were perhaps more thinly defended than normal.
In the same year - 406 - Honorius urged the
provinciales of the west to take up arms in their own defence
and offered freedom to slaves who volunteered to join them. Seeing
the writing on the wall, the army in Britain first elevated a soldier
named Marcus, but they murdered him when he didn't meet their
Next they elevated a Briton named Gratian, who appears
to have been a civilian and was probably a member of the Romano-British
upper class. During the chaos in Gaul, as Franks, Alani, and Romans
fought Vandals, Alani, and Suevi near the Rhine, Gratian's four month
reign came to an end with deposition and murder.
His main failing seems to have been his refusal to
cross the Channel to defeat the invading barbarians before they could
launch an invasion of Britain. This is what the ruling classes in
Britain most feared, and they expected to receive little help from the
Seeing the division and confusion caused by the
barbarians in Gaul, the army of Britain may have believed that Britain
should not stand alone but should be part of a united Gallic province,
as it had been previously under Clodius Albinus (193-197) or Magnus
Barbarians in the form of the Vandals, the
Suevi, and the Alani crossed the Rhine en masse at Mainz
(above) on the last day of AD 406, bringing chaos to Roman Gaul.
They were attacked by Frankish tribes who had already settled on
the west bank of the Rhine, and faced defeat until the Alani came
to their aid.
The very fact that they believed they could make
an attempt of the traditional type on the Continent suggests the
army in Britain felt its own strength still to be sufficiently
great to overawe and win the support of the surviving Roman and
allied forces in Gaul and Germany, or to defeat them if they
remained loyal to the imperial government at Ravenna.
Emperor Constantine III steps forward
This does not support the view that Britain had
been drained of troops by Stilicho in 401 (or if it had been, that
they had not been replaced). When the Britons selected Constantine
III, Sozomen, an historian of the Christian church in the fifth
century, thought it was because the great name he bore suggested
that he would win good fortune in any attempt to grasp the imperial
throne. Good fortune played an important part in how Roman troops
viewed their leaders.
Whatever the army's motives, Constantine moved
swiftly from Britain into Gaul before the barbarian horde of 406
could take the coast, sending officers in advance of him to secure
the support of remaining Roman or allied forces.
In the event, the barbarians turned south, and
Constantine's forces instead faced some stiff fighting against
loyalist forces, which they overcame. Constantine quickly took
over the administration of Gaul and set about repairing the Rhine
While he could not bring under control the
barbarians who were moving about in Gaul, he sent his son Constans
as Caesar and his British general Gerontius to secure Hispania in
a swift campaign. While, shortly before his own execution, Stilicho
tried to stir up some barbarians in Gaul against Constantine, by
the end of 408 or the start of 409 Honorius was forced to recognise
Constantine as Augustus and that year held the consulship jointly
The Saxon Shore was probably secure when Constantine left
It looked for the moment as if the army had made
the right choice. They had again made Britain part of a united
Gallic prefecture under firm Roman control. In Constantine III they
had a properly legitimised emperor who owed his elevation to them and
whose Continental forces contained senior officers from their own
There is absolutely no hard evidence that Constantine
withdrew the garrison from Britain at this time to reinforce himself
in southern Gaul. True, he probably took some frontline army units with
him, but it would make the most sense if he tried to balance the
disposition of his forces in the traditional way, in order to secure
all of his borders and territories. It would make no sense to deplete
Britain at a time at which he drew a large amount of support from the
However, while Trier had been the seat of Roman
central power in Gaul for more than a century, Constantine found
it had been moved very far south, to Arles, a transfer that had
probably only just happened as a result of the barbarian invasion
of 406. The transfer was as yet incomplete - the mint at Trier
continued to produce coins both for Constantine and his successor,
Jovinus. The result, though, was that Constantine's government was
much more distant from Britain that it would have been for Magnus
It doesn't seem to have taken the administration
in Britain long to see that Constantine's Gallic empire was now
very much focussed on the Mediterranean rather than the north,
something the Britons would not have been overjoyed to learn.
Other problems further complicated the issue.
With Constantine now the recognised joint Augustus,
the wandering barbarian tribes entered Hispania and disrupted his
empire. Gerontius rebelled and raised his own puppet emperor,
beginning preparations to march north and challenge his former
Coin bearing the image of Constantine III with Roma seated
on the rear side holding Victory, right, and spear, left
At the same time, (late 408) barbarians in the form
of Saxons launched a serious and destructive attack on Britain.
Constantine probably did not have the troops to spare to deal with
this emergency because when Gerontius revolted the bulk of the army
was with him in Hispania.