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History => Ancient and Medieval History => Topic started by: Imperial Dave on August 04, 2017, 05:03:39 PM

Title: GDP map of the Roman Empire
Post by: Imperial Dave on August 04, 2017, 05:03:39 PM
http://brilliantmaps.com/roman-empire-gdp/

here's a really interesting talking point....GDP of the various provinces of the Roman Empire and how it compares (or not) to today
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 04, 2017, 06:00:55 PM
Quote from: Holly on August 04, 2017, 05:03:39 PM
http://brilliantmaps.com/roman-empire-gdp/

here's a really interesting talking point....GDP of the various provinces of the Roman Empire and how it compares (or not) to today
interesting
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 04, 2017, 07:45:04 PM
Not entirely convinced it can be compared like for like but very interesting nonetheless
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 05, 2017, 03:29:18 PM
It is reminiscent of the Imperium Romanum II province values in Period I and II (early Empire).  Curiously, the site terms it a GDP per capita map as opposed to a GDP map - were the inhabitants of the higher-yielding provinces individually so much more productive than those elsewhere?

One may also consider that the skyrocketing value assigned to Italy presumably reflects the tendency of Rome to attract (or compel) resources from elsewhere rather than the Italians themselves being super-productive.
Title: Re: GDP map of the Roman Empire
Post by: Dangun on August 06, 2017, 03:09:23 AM
Quote from: Patrick Waterson on August 05, 2017, 03:29:18 PMIt is reminiscent of the Imperium Romanum II province values in Period I and II (early Empire).  Curiously, the site terms it a GDP per capita map as opposed to a GDP map - were the inhabitants of the higher-yielding provinces individually so much more productive than those elsewhere?

Yes they were. We can tell that from quotes concerning tax revenues.

GDP is very difficult to estimate in pre-modern societies, making the population estimate look simple by comparison.
So I'd suggest a comparison between then and now is basically baseless/pointless.
But... as we've explored in another thread, a comparison of province to province is much more interesting.
I would like to know how they cam up with the GDP estimate.

To move closer to our area of interest, I think a province's GDP per mile of imperial border might be more interesting.
Sort of a what we get / what we lose kind of ratio.

Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 06, 2017, 08:16:08 AM
Always going to be difficult in terms of like for like comparisons. As suggested in inter province one is of more use. What about outside the empire...how do we attempt to validate that
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 06, 2017, 09:36:10 AM
Quote from: Dangun on August 06, 2017, 03:09:23 AM
To move closer to our area of interest, I think a province's GDP per mile of imperial border might be more interesting.

The first and most obvious observation is that there is a massive difference between East and West.  In the east itself, Commagene and Syria have the same GDP categorisation as Asia and Galatia but very different 'border miles'.  Incidentally, should one count desert borders (important for Libya, Africa etc.) and if so how should these be weighted compared to borders adjoining Mesopotamia and along the Rhine and Danube?

The next observation is that in the west there seems to be a clear correlation between the GDP of a province and the length of time it has spent in the Empire.  This is worth bearing in mind when wondering about the cost of maintaining legions on borders.

Some provinces have no imperial border, and hence would have infinite GDP by comparison with the remainder.  These, of course, were usually the provinces without legions.

To be meaningful, we really need to look at the Empire as a whole, otherwise there is a danger of seeing it through the eyes of a consultant advising the Romans to concentrate on their economic core competences and letting the frontier provinces go as uneconomic, which would leave several populations of unreformed barbarians whose population had grown, who were familiar with Roman organisation and weaponry and who may have felt they wished to settle some old scores.  (Remember Civilis! ;))
Title: Re: GDP map of the Roman Empire
Post by: Dangun on August 06, 2017, 04:42:50 PM
Quote from: Patrick Waterson on August 06, 2017, 09:36:10 AMThe next observation is that in the west there seems to be a clear correlation between the GDP of a province and the length of time it has spent in the Empire.  This is worth bearing in mind when wondering about the cost of maintaining legions on borders.

This makes some economic sense - cumulative investment e.g. roads, aqueducts, ports etc should increase GDP. It is probably an incomplete explanation, but does make some sense.

Quote from: Patrick Waterson on August 06, 2017, 09:36:10 AMTo be meaningful, we really need to look at the Empire as a whole, otherwise there is a danger of seeing it through the eyes of a consultant advising the Romans to concentrate on their economic core competences and letting the frontier provinces go as uneconomic

I don't see why this is a danger, when it may simply be the case that some provinces are uneconomic. Such a question seems pretty simple to answer too.

We can complicate the analysis by saying, its not that simple, for example, we might want to argue that we have to hold all this uneconomic German territory to keep X, and Y economic territory. But in some cases it is pretty simple. For example, was Britain an economic positive or negative? Was Mesopotamia an economic positive or negative? In these cases, there is certainly an answer, we might not have the answer, and the range of possibilities is attractively binary.
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 06, 2017, 09:14:33 PM
Then, of course, we have places which are an economic negative but a security positive, like Germania Inferior and Superior.  Interestingly, the neither-one-thing-nor-the-other provinces (Agri Decumates and Dacia) were the first to be abandoned, suggesting the Romans did their own cost-benefit analyses, admittedly when under stress.

In the east, the provinces seem to have been worthwhile economically but subject to competition from whoever ruled the Persian territories at the time.  The result was much money spent not only acquiring and retaining provinces but also, as Rome increasingly took over direct administration as opposed to letting local princes do it, fortifying and otherwise securing the borders.  There was a good reason for this: when the defences failed (as in the mid-3rd century AD) the Sassanids penetrated deep into the economic heartland of the east (notably Syria) and caused great loss and damage.

Part of the imperial defence system was, where possible, to secure the chap beyond the border as a client king.  He then kept at arms length his immediate neighbours, which in turn discouraged him from becomong too interested in testing out the Empire's defences.  When this system broke down, it became necessary to establish limitanei - a border force which dealt with small parties of barbarians and provided a 'trip-wire' warning system for larger incursions - this in addition to the legionary armies at various stations.

By the time of Diocletian's successors, the majority of the good troops were no longer located in the frontier provinces, but held in palatini armies around major cities in the wealthier provinces, to be committed when required.  This of course spread the maintenance load (although it all came form the Imperial treasury in the end) and in addition adjusts the costing for various provinces, because no longer can one notionally assign the costs of defending the Empire to the frontier provinces.

Quote from: Dangun on August 06, 2017, 04:42:50 PM
We can complicate the analysis by saying, its not that simple, for example, we might want to argue that we have to hold all this uneconomic German territory to keep X, and Y economic territory. But in some cases it is pretty simple. For example, was Britain an economic positive or negative? Was Mesopotamia an economic positive or negative? In these cases, there is certainly an answer, we might not have the answer, and the range of possibilities is attractively binary.
Britain was an economic positive , probably from the 2nd century AD, certainly in the 3rd when under Carausius it left the Empire, flourished and was definitely missed until reclaimed by Constantius Chlorus.

Mesopotamia, when held, would have been an economic positive (which is why Parthians, Persians etc, always strove to hold it), but the problem was that from the Roman point of view it was a political negative: once conquered by Trajan, it comprehensively revolted, which led Hadrian to withdraw from it entirely.
Title: Re: GDP map of the Roman Empire
Post by: Dangun on August 07, 2017, 01:04:14 AM
Quote from: Patrick Waterson on August 06, 2017, 09:14:33 PM
Britain was an economic positive , probably from the 2nd century AD, certainly in the 3rd when under Carausius it left the Empire, flourished and was definitely missed until reclaimed by Constantius Chlorus.

Mesopotamia, when held, would have been an economic positive (which is why Parthians, Persians etc, always strove to hold it), but the problem was that from the Roman point of view it was a political negative: once conquered by Trajan, it comprehensively revolted, which led Hadrian to withdraw from it entirely.

I may be misunderstanding your intention, but it sounds as though you are suggesting - particularly in regards to Mesopotamia - that you are suggesting that any territory is economically positive... if only it was peaceful. But that's the problem with province Mesopotamia, you cannot expect it to be peaceful and productive because you will be constantly at war with angry Persians and Parthians throwing resources away on something you can't hold.

We can tell that there were a lot of uneconomic / economically negative provinces simply from how close to balanced the budget was, and with Italy and Egypt so productive there are economic sinks to be identified.
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 07, 2017, 08:39:05 AM
Quote from: Dangun on August 07, 2017, 01:04:14 AM
I may be misunderstanding your intention, but it sounds as though you are suggesting - particularly in regards to Mesopotamia - that you are suggesting that any territory is economically positive... if only it was peaceful.

Almost any territory - they did start out self-sustaining before the Romans acquired them.  Conversely, the composite Agri Decumates (https://en.wikipedia.org/wiki/Agri_Decumates) were a frontier region not based on a specific local population and culture, an artificial entity populated by settlers, and seemingly not worth the effort of recovery after Gallienus' reign.  Ultimately, the effort of recovery seems to have been the principal criterion for retention until Dacia (https://en.wikipedia.org/wiki/Roman_Dacia) was knowingly and deliberately abandoned c.275 BC; by this time it had been combed by repeated barbarian invasions and Aurelian seems to have considered was not worth the trouble of rebuilding when its surviving personnel would be more useful fleshing out similarly-depleted Moesia.  It is nevertheless worth noting how much effort the Roman put into making Dacia 'profitable'.

Quote
But that's the problem with province Mesopotamia, you cannot expect it to be peaceful and productive because you will be constantly at war with angry Persians and Parthians throwing resources away on something you can't hold.

But this will be true of whatever region is adjacent to the Parthian (or Sassanid) Empire.  The specific problem with Mesopotamia was not proximity to a (recently-defeated) foe, but the fact that it rose in rebellion so comprehensively that Hadrian, who later was prepared to commit ten legions and several years to suppressing the Bar-Kochba revolt in Judaea, considered it a lost cause and withdrew.

Quote
We can tell that there were a lot of uneconomic / economically negative provinces simply from how close to balanced the budget was, and with Italy and Egypt so productive there are economic sinks to be identified.

Perhaps not so much provinces as processes: Imperial tax collection left much to be desired, as shown when Julian overhauled the administration of Gaul and had everything running for a capitation tax of 7 gold pieces as against the previous 25.  This was during a time of intensive campaigning against the German tribes, who had been invading and despoiling the province, so it was hardly at peak performance.

Where my main reservations lie is in a purely economic or financial analysis: this tends to ignore vital considerations (political, both with regard to threats on the borders and the internal stability of provinces) and overlooks the possibility of internal improvement making the system more effective.

We should perhaps also note that when the Empire was expanding in the 1st century BC/early 1st century AD, some territories, notably Germania and Illyria (and even areas of Hispania) required much force to subdue, such that the province was definitely a financial loss.  However subduing these provinces was essential for the integration of the Empire (Illyria so that east-west travel need not be wholly by sea, for example) and the only province of the three not ultimately subdued was Germania.  Why?  Because it launched a successful rebellion and subsequently avoided decisive military defeat.

One serious problem with attempting to evaluate each province as a 'defence liability' is that the legions have to be paid wherever they are, and another very serious consideration is that they are not the only item dealt with by the Imperial exchequer.  Buildings, entertainments and prestige projects generally (plus the corn distribution for the citizenry of Rome) all featured as expense items, and under some early emperors expenditures got out of hand.  It is noticeable how the exchequer filled up under Tiberius, was emptied by Caligula, restocked by Claudius (despite the supposed expenses of campaigning in Britannia) and squandered by Nero, Otho and Vitellius before being refilled by Vespasian.  Personalities mattered, and converted the underlying economics into an easy positive balance or a dead loss.  Yet the fact that sensible rulers were well able to build up a surplus shows that the underlying economics were sound, whether or not some individual provinces might be considered 'loss-makers', which is itself a questionable assumption given the Roman determination to make provinces pay.

This goes back to the old Biblical question of how you set a level of tribute (taxation is basically tribute with a different middleman).  Back in Biblical days, most civilisations seem to have had extensive bureaucracies which assessed each man individually.  Rome, once the Empire became settled, seems to have subcontracted the procedure but the essential approach was the same.  In the later Empire, there seems to have been a 'collective entity approach' in that taxpayers were grouped into units, and each unit would pay a level of tax determined by the 'needs' of the Empire - this is the assessment Julian so dramatically reduced in Gaul during his rule there.  The point here is that if a province was deemed uneconomic, its yield could be raised to the level of being economic - obviously only so far before it became ruined, but there was an element of flexibility there.  And this flexibility need not have a direct relationship to 'per capita GDP': the driving force was a perceived need for additional revenue.

And this concludes the lecture ... ;)
Title: Re: GDP map of the Roman Empire
Post by: Duncan Head on August 07, 2017, 09:04:59 AM
Quote from: Patrick Waterson on August 07, 2017, 08:39:05 AMIt is nevertheless worth noting how much effort the Roman put into making Dacia 'profitable'.

Wikipedia - https://en.wikipedia.org/wiki/Roman_Dacia#Economy - and I have made no effort to check out its sources - suggests that "Evidence points to the closure of the gold mines around the year 215 AD". Is the story of Dacia perhaps simply that for the first century or so it was very profitable, and worth the considerable military investment to secure it, but ceased to be so when the gold ran out?
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 07, 2017, 03:24:49 PM
Always going to be a driver....precious metals and other important commodities. One wonders why Britain remained high on the empires agenda when it wasn't all that profitable...ie the high level of maintenance required
Title: Re: GDP map of the Roman Empire
Post by: Mark G on August 07, 2017, 04:21:30 PM
Interesting though Duncan.

I would have thought defending the Danube was the reason, but exhausting the mines may better fit the chronology .

Can we test it?

And were the romans much good at finding new mines?
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 08, 2017, 01:39:30 AM
Quote from: Duncan Head on August 07, 2017, 09:04:59 AM
Is the story of Dacia perhaps simply that for the first century or so it was very profitable, and worth the considerable military investment to secure it, but ceased to be so when the gold ran out?

Possibly, although it also had salt, iron, silver, and copper mines, various useful building stones and several flourishing manufacturies.  While the gold running out doubtless made it less of a - erm - gold mine, there seems to have still been plenty of economic life there.  The mines ran out c.AD 215; the Romans ran out c.AD 275.  Sixty goldless years seems a long time to hold a supposedly impecunious province.

What does seem to have finished it off was the depopulation caused by a combination of plague and repeated barbarian invasions, which caused Aurelian to pull the plug.

The province of Dacia, which Trajan had formed beyond the Danube, he gave up, despairing, after all Illyricum and Moesia had been depopulated, of being able to retain it. The Roman citizens, removed from the town and lands of Dacia, he settled in the interior of Moesia, calling that Dacia which now divides the two Moesiae, and which is on the right hand of the Danube as it runs to the sea, whereas Dacia was previously on the left. — Eutropius IX.15

Quote from: Holly on August 07, 2017, 03:24:49 PM
One wonders why Britain remained high on the empires agenda when it wasn't all that profitable...ie the high level of maintenance required

It was nevertheless considered worth reconquering, and, while the Empire remained intact, retaining.  It seems to have had virtues over and above a simple positive cash balance: Julian brought in significant quantities of grain from Britannia to restock towns along and near the Rhine, which suggests Britain was an important grain-producing area in the late Empire.  Also, the Bordeaux wine merchants needed someone who would pay for their produce ...  ;)
Title: Re: GDP map of the Roman Empire
Post by: Dangun on August 08, 2017, 02:51:43 AM
Quote from: Patrick Waterson on August 07, 2017, 08:39:05 AM
Almost any territory - they did start out self-sustaining before the Romans acquired them.

This is a good point and always worth remembering.  :)

Quote from: Patrick Waterson on August 07, 2017, 08:39:05 AM
Where my main reservations lie is in a purely economic or financial analysis: this tends to ignore vital considerations (political, both with regard to threats on the borders and the internal stability of provinces) and overlooks the possibility of internal improvement making the system more effective.

Agreed. Financial factors are never very good at proximate explanations, but its a very powerful tidal factor.

Quote from: Holly on August 07, 2017, 03:24:49 PM
One wonders why Britain remained high on the empires agenda when it wasn't all that profitable...ie the high level of maintenance required

This is an interesting question and I can't recall a lot of Roman literature that talks about it. Maybe its like a Falkland-Islands-Affect - once its Roman, as a matter of principle you stubbornly resist giving it up, irregardless of the financial impact? Politically too, no one wants to be remembered as the leader who gave up said territory...

http://www.businessinsider.com/falkland-islands-cost-2012-2 (http://www.businessinsider.com/falkland-islands-cost-2012-2) suggests the cost of defending the Falklands' is about US$35,000 per inhabitant. Completely uneconomic. But possibly a necessary part of defending Greater London??  ;)
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 08, 2017, 12:03:09 PM
I do suspect that this is a lot to do with it to be fair. What was the parallel with other territories that the Romans did give up like Germans inferior and parts of Dacia?
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 08, 2017, 10:02:53 PM
Quote from: Holly on August 08, 2017, 12:03:09 PM
What was the parallel with other territories that the Romans did give up like Germans inferior and parts of Dacia?

The Romans did not give up Germania Inferior until after AD 408, and even then hung on to it indirectly by letting Franks settle there and keeping them as allies (most of the time).  What they gave up was the Agri Decumates, a settlement frontier zone between the Germanias and Rhaetia, and they did so only in the context of the Crisis of the Third Century, when widespread barbarian invasions, plague and Gallienus practically destroyed the Empire (Aurelian pulled it back together c.AD 272-274).  With the Empire back in hand, Aurelian let go both Dacia and Agri Decumates, which were:
1) Rome's most recent acquisitions
2) More exposed than any other provinces
3) Seriously depopulated (along with the rest of the Empire).

Somewhere in this combination of factors is probably the common reason for abandonment.  The Empire had lost something like half its population, and what there was needed to be used effectively.  Aurelian seems to have pulled the plug on the basis of population requirements as much as anything else; lack of sufficient people meant that something had to go, and these most exposed provinces drew the short straw.  My best guess is he decided he could afford to dispense with these but could not afford to abandon anything else.

Earlier on, Hadrian had rationalised Trajan's Dacia by granting the plains area to the Rhoxolani, in effect trading a wide extent of grass for a useful client state.  This meant that the U-shaped gap in the frontier was not a problem as it was inhabited by friendlies.  Naturally, a century later, when no longer inhabited by friendlies, it did become a problem, but this arose from failure/inability to adapt to a changed situation.
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 08, 2017, 10:33:20 PM
if manpower and population was an issue for relinquished areas....why was Britain kept...especially since it was a proverbial pain in terms of breakaway emperors
Title: Re: GDP map of the Roman Empire
Post by: Dangun on August 09, 2017, 06:43:55 AM
Pieces of the middle east also periodically fell off.

Quote from: Patrick Waterson on August 08, 2017, 10:02:53 PM
2) More exposed than any other provinces
3) Seriously depopulated (along with the rest of the Empire).

I'd note that 2 and 3 are quite closely related to costs and revenues.  :)
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 09, 2017, 10:01:01 AM
Quote from: Holly on August 08, 2017, 10:33:20 PM
if manpower and population was an issue for relinquished areas....why was Britain kept...especially since it was a proverbial pain in terms of breakaway emperors

Precisely because it was populous enough to support breakaway emperors ...

Quote from: Dangun on August 09, 2017, 06:43:55 AM
Pieces of the middle east also periodically fell off.

Notably Palmyra, and again notably in the 3rd century crisis.  This too was regained by Aurelian, although in regaining Palmyra he destroyed its prosperity so it became more of a geographical footnote. 
Quote
Quote from: Patrick Waterson on August 08, 2017, 10:02:53 PM
2) More exposed than any other provinces
3) Seriously depopulated (along with the rest of the Empire).

I'd note that 2 and 3 are quite closely related to costs and revenues.  :)

I give you that.

They are also related to the ability to maintain a coherent economy and infrastructure, and this rather than any idea of a province paying its way or otherwise seems to have been Aurelian's criterion for abandonment.  We are after all talking about not a business but a government organisation. ;)
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 09, 2017, 10:33:06 AM
Quote from: Patrick Waterson on August 09, 2017, 10:01:01 AM
We are after all talking about not a business but a government organisation. ;)
In this period, given their grasp of economic theory, would there be that much difference? There are times when you feel the Empire was run pretty much as you'd run a large landed estate, which is what many of the Emperors and their advisers effectively did for a living anyway  8)
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 09, 2017, 09:10:22 PM
Quote from: Jim Webster on August 09, 2017, 10:33:06 AM
Quote from: Patrick Waterson on August 09, 2017, 10:01:01 AM
We are after all talking about not a business but a government organisation. ;)
In this period, given their grasp of economic theory, would there be that much difference? There are times when you feel the Empire was run pretty much as you'd run a large landed estate, which is what many of the Emperors and their advisers effectively did for a living anyway  8)

And land was seen as the one asset with enduring value.  My thought was mainly about contrast with modern cost/benefit business analysis and accounting methods; as you rightly indicate, the Romans would be very unlikely to think the modern way.  Their idea of empire management would be less about disposal of loss-making assets and more about sending the tax gatherers out again to make up any shortfall.
Title: Re: GDP map of the Roman Empire
Post by: Erpingham on August 10, 2017, 10:34:07 AM
It's a discussion we have had before, but as you say, it is dangerous to back-project the methods of modern capitalism onto ancient empires.  I would suggest that the Empire became the natural order of things and maintaining it was the Roman way.  Once somewhere had been added to the Empire, it was the Emperor's duty to maintain it in the Empire.  Ground was ceded only with great reluctance and not based on a set of Excel spreadsheets.
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 10, 2017, 10:45:04 AM
Quote from: Erpingham on August 10, 2017, 10:34:07 AM
It's a discussion we have had before, but as you say, it is dangerous to back-project the methods of modern capitalism onto ancient empires.  I would suggest that the Empire became the natural order of things and maintaining it was the Roman way.  Once somewhere had been added to the Empire, it was the Emperor's duty to maintain it in the Empire.  Ground was ceded only with great reluctance and not based on a set of Excel spreadsheets.

so how does the likes of Hadrian fit in ie in terms of trying to define and 'fix' the outer markers of the empire....would GDP/wealth accrual come into the decision making process? 
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 10, 2017, 01:05:48 PM
Quote from: Holly on August 10, 2017, 10:45:04 AM
Quote from: Erpingham on August 10, 2017, 10:34:07 AM
It's a discussion we have had before, but as you say, it is dangerous to back-project the methods of modern capitalism onto ancient empires.  I would suggest that the Empire became the natural order of things and maintaining it was the Roman way.  Once somewhere had been added to the Empire, it was the Emperor's duty to maintain it in the Empire.  Ground was ceded only with great reluctance and not based on a set of Excel spreadsheets.

so how does the likes of Hadrian fit in ie in terms of trying to define and 'fix' the outer markers of the empire....would GDP/wealth accrual come into the decision making process?
I suspect that it would be a mix of factors. The line of the frontier could be decided by geography (rivers are good, you know where they are, also they make excellent supply lines for getting bulk supplies to frontier garrisons stationed along them.)
Title: Re: GDP map of the Roman Empire
Post by: Erpingham on August 10, 2017, 01:35:21 PM
To be clear, I don't think there were no cost/benefit calculations.  Just that financial considerations were not the sole element.  I also doubt whether per capita GDP was the financial factor at the top of everyone's minds.  Sustaining the elite that ran the Empire was probably a more active concern.
Title: Re: GDP map of the Roman Empire
Post by: RichT on August 10, 2017, 02:03:02 PM
I can't speak for Romans, but to go off on a tangent, for Hellenistic kings it was a key part of royal ideology that a king should maintain and ideally add to the territories bequeathed to him by his predecessor. So once a territory was 'in', for whatever reason (and claiming territories 'won by the spear' was another key part of royal ideology), there would be a strong onus on subsequent kings to keep it in. No doubt if a territory turned out to pay lousy taxes, be full of rebellious subject, or require ruinous expense to defend, these rules could suddenly be found to be more like guidelines, but the shape of a Hellenistic kingdom wouldn't be determined primarily by considerations of cost/benefit analysis, GDP etc.
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 10, 2017, 02:32:24 PM
Quote from: RichT on August 10, 2017, 02:03:02 PM
I can't speak for Romans, but to go off on a tangent, for Hellenistic kings it was a key part of royal ideology that a king should maintain and ideally add to the territories bequeathed to him by his predecessor. So once a territory was 'in', for whatever reason (and claiming territories 'won by the spear' was another key part of royal ideology), there would be a strong onus on subsequent kings to keep it in. No doubt if a territory turned out to pay lousy taxes, be full of rebellious subject, or require ruinous expense to defend, these rules could suddenly be found to be more like guidelines, but the shape of a Hellenistic kingdom wouldn't be determined primarily by considerations of cost/benefit analysis, GDP etc.
I think the Hellenistic kingdoms, certainly the Seleucids, are a good example in that there were degrees of 'in'.
Some places would be autonomous but make regular generous gifts and allow their foreign policy to be guided by the King, whereas other places would have garrisons, pay tribute and obey orders.
Then you'd have tribal people within the Empire who might pay a nominal tribute, receive gifts to help them through bad winters and discourage them from having to raid, and would supply troops when asked and probably recruits even in peacetime
Areas could move between these various degrees but would still be 'in'
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 10, 2017, 05:08:20 PM
so in the Hellenistic world, a mixture of prestige, money opportunities and a flexible approach to the 'arrangements' used on a local level. In the Roman world more a case of pride/prestige and a solidification of 'this bit is mine'?
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 10, 2017, 06:42:54 PM
Quote from: Holly on August 10, 2017, 05:08:20 PM
so in the Hellenistic world, a mixture of prestige, money opportunities and a flexible approach to the 'arrangements' used on a local level. In the Roman world more a case of pride/prestige and a solidification of 'this bit is mine'?
I'm not sure about the Romans and 'solidification' in that there is now evidence that the Romans had troops patrolling regularly beyond the line of the frontier, forts in Scotland north of the border (which obviously couldn't have been held against a hostile populace without armed convoys fighting their way through with supplies) seem to indicate fuzzy boundaries, there may have been Roman troops at the Nabataean Red Sea port of Leuke Kome. In North Africa the boundary seems to have relied of tribal leaders with Roman titles controlling areas inside and outside the Empire, and then you have the Ghassanids and Lakhmids contesting between them a broad border area

Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 10, 2017, 08:43:45 PM
The whole client king/client state system practised under the Roman Empire seems to have been an integral part of maintaining borders beyond the borders, so to speak.  As Jim points out, Hellenistic kingdoms also had degrees of 'in', where rule shaded down to influence and was blended with alliance.
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 11, 2017, 09:56:39 AM
Quote from: Jim Webster on August 10, 2017, 06:42:54 PM
fuzzy boundaries,

possibly the most dangerous kind of border for the empire
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 11, 2017, 10:21:11 AM
Quote from: Holly on August 11, 2017, 09:56:39 AM
Quote from: Jim Webster on August 10, 2017, 06:42:54 PM
fuzzy boundaries,

possibly the most dangerous kind of border for the empire
Yes, because they always tempt you to go that little bit further
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 11, 2017, 09:11:00 PM
Quote from: Jim Webster on August 11, 2017, 10:21:11 AM
Quote from: Holly on August 11, 2017, 09:56:39 AM
Quote from: Jim Webster on August 10, 2017, 06:42:54 PM
fuzzy boundaries,

possibly the most dangerous kind of border for the empire
Yes, because they always tempt you to go that little bit further

Or think that if you ceded ground it was only temporary...
Title: Re: GDP map of the Roman Empire
Post by: Jim Webster on August 11, 2017, 10:02:49 PM
Quote from: Holly on August 11, 2017, 09:11:00 PM
Quote from: Jim Webster on August 11, 2017, 10:21:11 AM
Quote from: Holly on August 11, 2017, 09:56:39 AM
Quote from: Jim Webster on August 10, 2017, 06:42:54 PM
fuzzy boundaries,

possibly the most dangerous kind of border for the empire
Yes, because they always tempt you to go that little bit further

Or think that if you ceded ground it was only temporary...
Merely stepping back to butt harder  ::)
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 12, 2017, 07:12:26 PM
An opportunity to fill one's coffers :)
Title: Re: GDP map of the Roman Empire
Post by: Patrick Waterson on August 12, 2017, 07:58:35 PM
Which incidentally might skew the GDP map.
Title: Re: GDP map of the Roman Empire
Post by: Imperial Dave on August 13, 2017, 09:05:22 AM
good point...

GDP could therefore be very very (very) volatile!