To everyone that thinks Rome was bound to stay squatted on the shores of the Med:
...ask Julius Caesar. The guy changed everything. It is his historical accomplishment to have thoroughly linked Northwestern Europe to the Antique World.
If Octavian had succeeded in conquering Magna Germania, the same would have applied to Central Europe (regard his other acquisitions in the Alpine/Danube region).
and by doing so, the empire gradually makes itself much stronger, while making present and future enemies much weaker.
This is an understanding of international relations the Romans were quite familiar with.
The problem with ensuring TLs where the Empire of Caesar Augustus survives is that the Roman Empire's prosperity rested on two circumstances that collapsed the OTL Western Empire and ultimately did in the Eastern one, too: the Roman idea of a line of succession was whoever won the civil wars sparked by power vacuums. This was tolerable so long as only one enemy, be it Parthia, or be it various tribal confederacies, attacked the Empire as a whole at a single time.
If both of them did the civil war problem was rather likely to bite the Empire in the ass, which is what happened IOTL. If the Roman Empire is to survive, Caesar Augustus must come up with some variation of a workable succession plan.
*sigh* It is not as if nobody tried. Octavian was frantically searching for a legitimate and able heir and messed his whole family up in order to do so. Of course, his aim was to establish a dynasty to rule for.....a long time. This failed with Nero. And again, for the Flavians, with Domitian.
The concept of the "Adoptive Empire", created out of sheer despair by Nerva, could have been fine for a far longer time than three generations (not bad by modern standards either), had there have been a way to enforce and acknowledge such an adoption (e.g. through the Senate or the Priesthood), akin to the US amendment, IIRC, which doesn't allow a president to work without a vice-president. Such a procedure would have ruled out the historical and most other Commoduses.
Then Diocletian tried again with the 2.0 version of the concept, this time written in law but again only working in theory. Allowed him a damn fine retirement, though.
My point: civil war was not the ideal order of succession. Romans were not Clingons.
Oh absolutely, this is very important, too. IMO, the most important things to secure Rome's lasting success are, in rough order of importance:
A) Assimilate all of Germania up to the Vistula-Dniester line.
B) Achieve a largely stable succession method.
C) Conquer Mesopotamia (and hence cripple Parthia).
D) Develop a counterbalance...
I would like to add E), to institutionalize centres of higher learning which should not only encompass the classical virtues of education such as rhetorics and philosophy, but also allow for a professionalisation of the theory of engineering, shipbuilding, manufacturing, military doctrine and equipment, administration, architecture.
This is not a progess one IMPERATOR can achieve at his will, but would need a long-term committment and acceptance of society (also in the form of stipendiae for the gifted, but less wealthy). But imagine maybe 10 or 12 such centres throughout the empire! What a possibility for slow but steady technological progress! What a mass of professional cadres in all fields!
I'd switch it so that B and D are A and B and put C over A.
Fine point. First, bring your house in order before you try anything funny.
the Ottomans are the only ones who preserved a state more or less intact with a single type of dynastic-administrative structure for centuries.
In the end, not to their advantage. Systematical changes over time won't harm the empire if they mean more effective governance. Also, a change of dynasties isn't necessarily bad.
Essentially the Romans need a leadership luck-string of the sort possessed by the Prussians.
The Romans outdo the Prussians on that field already. How about Caesar / Octavian? Or Trajan - Markus Aurelius? I would even argue that throughout the whole era of the Pax Romana Rome was ruled rather skillfully for more than 200 years with the spectacular exceptions of Caligula (4 years) and Nero (14 years+1 year of civil war) - I even count Domitian among the competent, despite his paranoia.
The Prussians? Friedrich Wilhelm I plus Friedrich II, that makes a succesful (though personally ...err.....distant) father/son-combination. Apart from that, I do not give my blessings to the Hohenzollern except for the ability not to stand in the way of two perfect storms of talent, the badly needed reformers of 1806-15 and the Bismarck/Roon/Moltke-combo.
How will this happen? Who will do the building? Who will "settle down" tribes?
Errr....the same Roman specialists who inflated settlements into towns in Northern Europe in a way that one could say they built them from scratch?
The German tribes will settle down themselves. They are comparable mobile, but not purely nomadic. They are not genetically hindered from taking the opportunities contact with the Med-civilization allows them.
I would say, within Magna Germania, the network of cities would initially have to be looser than in other places. There are hardly places where cities like Col. Claudia Ara Agrippinensium (Cologne, 20,000 inhabitants) or Aug. Treverorum (Trier, 80,000 inhabitants) are imaginable for the first centuries.
There would be a handful of Col. Ulpia Trajana (Xanten, 10,000 inhabitants)- sized cities as seats of provincial administration, but rather characteristical would be small places for merchants and tradesmen with few small typically Roman installations (a moderate bath, a cosy forum, a theatre unlike the one in Xanten or Trier, but rather like the African one in "Gladiator"), with maybe 2-3,000 inhabitants.
What is far more important is the network of roads to be built.
But why would such a decision be made in the first place?
Megalomania?
Good point. Ask Augustus who pursued such a policy for 20 years and IMHO would have continued to do so, would he not have been a very old man when 9AD came.
it has no settlements- not even villages-
You argumentation on the process of Romanization is altogether valid. But along with Tacitus you probably exaggerate the beloved isolation of people living in Germania.
Also, there must have been stratification in society already in the 1st century - where else would someone like Arminius have come from? As elsewhere, Rome also in Germania relied on pro-Roman factions for support (ultimately failing in this case); but there were people who favoured Roman contact and who would have been willing to be agents of Romanization.
On the conquest in the 3rd/4th century - scenario. Why not? If we take into account a Roman Empire which made internal progress in order to avoid or mitigate the 3rd century crisis (at least not making everything worse by a breakdown of succession-systems), one could imagine a decision to break the crisis by a return to expansion. Or if the crisis is avoided, Rome just simply could do it. Even around OTL 235AD, Roman forces got engaged in a battle near the Harz mountain which is rather closer to Berlin than to Cologne.
I would estimate Germania is going to take at least six legions to pacify,
6 is easy. I would estimate 11.
On the other hand, reduce the legions on the Rhine from 5 to 2, the Pannonian legions from 4 to 2, re-distribute the 6 Legions in Moesia and Dacia in order to man the border on the Dnjestr and to control "Dacia Magna" (the whole region between Dnjestr, Danube and Carpathes).
This already gives you 5 Legions to control the area between Rhine and Vistula. 5 are IMHO for a long time only sufficient for the area between Rhine and Elbe/Moldau. For the rest I would estimate and additional 6, so your count suits again. For most of the "Pax Romana", this would mean a rise from 28 to 34 legions. In the longer run, this number could be slightly reduced again.
Now that means a rise by 25%. This is a lot, but not wholly out of order for the rise and fall of number of regions during the first two centuries AD.
In the end, again, I point out that the task is imaginable to be solved, but there is not much probability for it to happen for the reasons Giorgios to
ferverntly pointed out. To make Rome more durable,
it is far more important to make changes in its society than to expand it further (because, come on, it is pretty big already). If Rome would have
conquered Germania Magna and still would have fallen, we would debate now whether a Limes on the Volga River would have saved it, maybe.
The funny thing, though, is, when I imagine Rome even more wealthy, internally more stable and a bit more technologically progressive (I am not talking
gunpowder or railroads here, but stirrups, better agricultural methods e.g.)