Calling all armchair generals! Boudica's Last Stand.

[MonsGraupius]

given the Thames is almost impossible to cross... I could find no credible evidence of a ford across the Thames there...

You will see from the source I linked that the Thames is (or was) far from 'impossible to cross'. The ford at Cliffe, or another nearby, was known to the Britons (according to Dio) and was used by Caesar, the one at Lambeth might have been dificult to cross but was certainly not impassable, and in 1016 Canute was apparently twice driven back across the Thames at Brentford, it seems (Anglo Saxon Chronicle).

Whether you choose to believe these sources or not, you must surely concede that the Thames could not have been considered an impassable barrier, and even if Paulinus was inclined to surrender the entire province north of the river to the enemy and retreat to the coast he could not have done so with any safety.

Were he looking for a defensible position he would have headed for the nearest high ground, rather than split his army up trying to defend river crossings.

Which is almost certainly what he did...

Sorry, what you are tapping into is the heated "debate" that went on for years of people arguing where Caesar crossed of the Thames. I had to go through it all, checking what every one of these numerous suggestions were saying to find out not whether it was where Caesar crossed, but whether there was any credibility to any crossing point at all. I can't say I was impressed. Some were based on no more than "the boatman says its quite shallow here", not even one known crossing, no historical evidence.

Unfortunately, the standard of early writing on this subject, was of the form: "I've been told by the boatman it's shallow here" which them was written up as: "This is where Dio Cassius refers to Caesar crossing the Thames".

If you discount all the crossings for which there is no historical accounts, that leaves a handful of sites which may have been crossing points. London bridge is well known, you mention the ford at the Houses of Parliament, I mentioned Vauxhall, you mention Brentford and I also mentioned Chertsey (where the London fire brigade kindly retrieved my depth measuring equipment which became detached and started floating down the Thames). For info, there was zero evidence of a ford, but its still possible.

"Whether you choose to believe these sources or not, you must surely concede that the Thames could not have been considered an impassable barrier" I have studied the subject in great detail and at length with the Thames as a special study area, so I don't think you will get a better opinion on the subject of fording the Thames.

I have said that there were a handful of difficult to cross fording sites which were easy to defend using a small force and the combination of the extreme difficulty of crossing the Thames and the small force made it all but impassable to large armies.

I though St.Albans was North of London

I believe you wrote of *the* north, not just a northerly direction.

The attack on St Albans occurs chronologically after Paulinus's retreat from London, and so can neither have caused it nor influenced his strategic thinking at that point. 

Paulinus army when it exits Wales is stuck in the north with hostile tribes to the west, east and the Brigantes to the north. The Road to London is overrun by the Iceni. The Welsh tribes would likely have followed the army out. The Brigantes may have started preparing for war, and not on the Roman side.

The army in the north is caught in a British sandwich with the potential to be attacked by the three most aggressive British tribes. It may not all have ben revolting ... but the North was in the middle of the revolt. And the armies only chance of survival was to head south ... keeping away from the Iceni who had already mobilised.

I'm not sure where we got mixed up.

Apparently you wrote Belgae when you meant Brigantes.

The Brigantes, however, were not in revolt against Rome at this point.

But they were not exactly friendly to Rome, and they were quite capable of taking the opportunity to mobilise and push them out of the north.

The tribes of north Wales had just been crushed by a Roman campaign and were in no condition to rise in revolt imminently.

Not on their own ... but if they could negotiate with the Brigantes and Iceni to co-operate, and if they have time to mobilise more forces, then they had the opportunity to wipe out the Romans.

So, the army sitting in the North having escape Wales, has three enemies:
1. The Iceni, who are already mobilised and have tasted blood.
2. The Northern Welsh tribes, who were mobilised, but had been beaten ... but on home soil, where they could quickly regroup and re-enforce
3. The Brigantes, who probably had no particular love for the Iceni and Welsh, but who would love to have got rid of the Romans and again become top dog in the North.

Fortunately the roads out of North Wales tend to go east so, that having escaped Wales, an army heading due south is then protected by the mountains ... then further south by the Severn and border hills. So, heading down toward Gloucester and then Cirencester, means the army is protected from all the tribes who are most capable of going to battle with them.

The attitude of the Belgae to the Romans at this time is unknown. The Regii (probably) of the Silchester area were perhaps allies. The Catavellauni of St Albans were certainly pro-Roman, as the town had been made a Roman municipium. If Paulinus was looking for friends in the area, he would have headed for St Albans.

By the time he got to London, he didn't even know if his own army had also been attacked and wiped out. He was alone...

He had his troops with him. Tacitus tells us he marched to London 'with wonderful resolution', thinking he might 'choose it as a seat of war'.

He (i.e. the force he took to London) was alone. Given what happened to St.Albans and the Ninth, and the way people would be streaming into London to get to safety on the other side of the Thames, there would have been chaos on the roads, ... wagon loads of people with all the valuables ... with no Romans to keep order. It doesn't take a genius to work out what the lowest life of the Britons would be doing. It was a thieves and highwayman's dream come true ... whether you were Iceni or not.

As Paulinus gets to London with "wonderful resolution" ... or as we might say it: without time to stop, he's not exactly going to inspire the Britons out Robbing the Romans from desisting. He's the Roman authority fleeing to London with the Iceni about to swarm all over it.

A "seat for war" is a defensible position with secure supply lines. We are told London was not suitable, because there is a swarm of Iceni, about to arrive (in a few days).

So, where does he choose as his "seat of war" if not London? Colchester? No! Up Ermine street to Lindum where the Ninth came from ... unlikely and far too close to Iceni lands. Up Watling street to Deva? Why? Why not St.Albans, of it not, why Deva? Not exactly my favourite choice for a battle against the Iceni.

Which basically leaves either a retreat to Dover ... or making Calleva his seat of war. From Calleva, Paulinus can easily keep supplied the defensive line of the Thames to the east, and he has the ridgeway hills as well us the (boggy) upper Thames to the west forming defensive lines to Cirencester/Gloucester and he has relatively easy access to ports on the south coast as well as Gloucester and even up the Thames.

The Severn-Thames narrowing, now has the same strategic benefit as the Clyde-Forth narrowing of the Antonine wall or the Solway firth-Tyne Narrowing of Hadrians wall. Anyone who cannot see that the Thames-Severn narrowing is exactly where Romans set up their "seat for war", is really as blind as an Olm.

The Severn estuary and river form a barrier on his west to S.Wales, effectively cutting the S.Wales tribes out the war. The Iceni can now only attack Paulinus in force by crossing the upper Thames above Goring ... which puts an army at Calleva just in the right position to stop them. This is the same as Bar Hill and the other Agricolan forts on the Antonine wall. We even have the wall, in the form of the Thames and ridgeway hills or upper Thames.

his mad dash down to London

There was no 'mad dash' either to or from London. Surely we have at least established that by now!

Ok, he galloped with "wonderful resolution" ... which as it normally takes an army up to a week to move camp (as historical accounts testify), we can assume cavalry can do 30 miles a day .... but only with light packs and fresh horses. His infantry might do 15 miles a day on roads, but their luggage train would take 2-3 days to do that. They could ditch the luggage train, but only when moving through friendly area they controlled. So, it would actually be quicker for the infantry to ditch their luggage train and go via Cirencester & Calleva where they could arrange supplies and then to London, rather than go directly to London through territory overrun by the Iceni. Because to go through enemy territory they have to have nightly camps, they have no secure supplies, so have to take it all with them.

But ... to London ... and ... having galloped with "wonderful resolution" ... he presumably exhausted all his horses, and is now in London ... with the whole populace hitching up every available horse and cart piled full of everything they own to escape the Iceni. So, no fresh horses there! So how does he gallop with "wonderful resolution" back north, through the Revolting British barricades now blocking every main roads, where the Brits are stopping all the fleeing Romans and politely asked them to forgo all their valuables and any virginity.

Even if Paulinus was going to join up ... let's say to Venonae (between Coventry and Leicester)... with another "wonderful resolution" ... gallop ... wouldn't he have gone to the nearest secure settlement of Calleva first to get fresh horses and supplies? Then he would have headed to Cirencester and then north to Venonae?

Of course, by the time he gets to Venonae, Boudica will have crossed the Thames, Calleva will be burning like St.Albans. The Iceni will have Paulinus stuck in the centre of England in a town almost as far away as you can get from any port ... not even near a major river!

So, if he did go to Venonae, he is not going to choose that for his "seat of war". Instead does he head for London ... No. Lindum ... No. Cirencester ... not bad, but a long way from the Iceni ... which really only leaves a journey back to Calleva