Why does Stannis have so few men but a gigantic fleet

[Alden Rothack]

Stannis has 80 war galleys and another 80 transports not counting the smaller pirate ships

how does he only have 5000 fighting men

[Alester Florent]

Stannis's bannermen are all island lords with all their strength in their navy and few land forces. He was also Master of Ships, of course, so may have some ships from the royal fleet with him, and he has been seizing third-party ships for some time to reinforce his fleet. 

The 5,000 fighting men he has probably do not include oarsmen and sailors. They probably do include what we might term "marines", not that that distinction really exists in this context.

[Alden Rothack]

44 minutes ago, Alester Florent said:

Stannis's bannermen are all island lords with all their strength in their navy and few land forces. He was also Master of Ships, of course, so may have some ships from the royal fleet with him, and he has been seizing third-party ships for some time to reinforce his fleet. 

The 5,000 fighting men he has probably do not include oarsmen and sailors. They probably do include what we might term "marines", not that that distinction really exists in this context.

I agree that it doesn't include rowers and sailors but galleys in particular had large numbers of marines, even in peacetime and on ships not intended for war, on war galleys such as the romans and venetians had this was even more true with over a hundred marines per galley being the norm

Given the presence of pirates along the main trade routes even the 'civilian ships should have a few dozen each, though the lack of any on ships in the reach is odd to say the least

Stannis's army is too small to be counting the marines as well, either they aren't there or Renly being very horse centric isn't counting them because he thinks they don't matter

[PrettyLittlePsycho]

His realm has a long shoreline and also islands like Tarth.

They need to have a strong Navy just to move around.

[Alden Rothack]

17 minutes ago, PrettyLittlePsycho said:

His realm has a long shoreline and also islands like Tarth.

They need to have a strong Navy just to move around.

Which they don't have without marines to do the fighting

[Aldarion]

5 hours ago, Alden Rothack said:

Stannis has 80 war galleys and another 80 transports not counting the smaller pirate ships

how does he only have 5000 fighting men

4 hours ago, Alester Florent said:

Stannis's bannermen are all island lords with all their strength in their navy and few land forces. He was also Master of Ships, of course, so may have some ships from the royal fleet with him, and he has been seizing third-party ships for some time to reinforce his fleet. 

The 5,000 fighting men he has probably do not include oarsmen and sailors. They probably do include what we might term "marines", not that that distinction really exists in this context.

3 hours ago, Alden Rothack said:

I agree that it doesn't include rowers and sailors but galleys in particular had large numbers of marines, even in peacetime and on ships not intended for war, on war galleys such as the romans and venetians had this was even more true with over a hundred marines per galley being the norm

Given the presence of pirates along the main trade routes even the 'civilian ships should have a few dozen each, though the lack of any on ships in the reach is odd to say the least

Stannis's army is too small to be counting the marines as well, either they aren't there or Renly being very horse centric isn't counting them because he thinks they don't matter

I had done estimates here:

https://warfantasy.wordpress.com/2023/11/09/military-of-westeros-1-organization-and-manpower/

Quote

When Davos goes to visit Stannis at Dragonstone, there were three thousand men camped on the island. This likely did not include sailors of the fleet, which itself consisted of war galleys, carracks and cogs. Later, when besieging Storm’s End, Stannis has 5 000 men, of which 400 horsemen, light horse mostly. Unknown number of those are sellswords which Stannis was already gathering earlier, but Stannis’ own troops most likely number 3 000. Renly states that such a host would not survive the first charge of his vanguard – correctly, as it turns out, although not at the time he had predicted.

Fury, Lord Stannis’ flagship, has 300 oars on three decks, deck covered with scorpions, and catapults fore and aft; the only galley in existence larger than Fury was King Robert’s Hammer, at 400 oars. Other galleys mostly had cca 200 oars. Ser Imry organized his fleet in ten lines of battle, each with twenty ships – normal galley tactics would have had one or two lines of battle, so this is likely a result of the constrained space. Additional 15 ships were lost along the way, so original fleet would have numbered 215 ships. It should be noted that this does not include Lyseni sellsails, which remained outside the bay as a rear guard. Ser Imry is noted to have had “four times as many ships as the boy king”, leaving Joffrey 50 ships. Original Royal Fleet would have thus numbered 265 ships. From example of Fury, and the fact that galleys have oars in multiples of 100, it can be assumed that one deck has 100 oars, or 50 rows. Byzantine dromond had 35 oarsmen on deck on either side and 25 beneath – 35 and 25 rows, respectively – at 32 meters length. As Westerosi galleys have covered decks, length of Westerosi galley might be 50 – 60 meters. Large Byzantine dromond had 230 rowers and 70 marines, and likely 170 oars. Out of 20 ships Davos lists, one has three hundred oars, two have two hundred oars, and 17 have a hundred oars. As Davos had noted nine particularly large galleys at Dragonstone, this disposition can be assumed to have been duplicated in all ten divisions. Assuming disposition similar to Byzantine dromond – two rowers per oar at third deck and one per oar at lower two decks, as well as soldiers as 30% of number of rowers – 300-hundred oar galley would have 400 rowers and 120 soldiers, 200-oar galley would have 200 rowers and 60 soldiers, and 100-oar galley would have 100 rowers and 30 soldiers. This is supported by the fact that Davos’ 100-oar galley is specifically noted to have had 100 rowers. Thus, each division of 20 ships would have had 2 500 rowers and 750 soldiers. Stannis’ fleet – 10 divisions – would have had 25 000 rowers and 7 500 soldiers. Original Crown fleet of 260 galleys would have had 32 500 rowers and 9 750 soldiers.

City Watch had 2 000 men during Robert’s reign, though these were not truly soldiers. Number was eventually expanded by Joffrey to 6 000, though most of them were useless. Tyrion had 300 “knights, squires, men-at-arms) at King’s Landing in addition to City Watch, though these may have been Lannister troops, as well as 800 sellswords.

RPG game endorsed by George Martin gave Crownlands 10 000 – 15 000 men, however. Rhaegar had 40 000 men, of which 10 000 were from Dorne and maybe 10 000 from Reach and 5 000 other loyalists, with Crownlands likely at 15 000 men. As such, division would be as follows:

Mainland: 12 000 infantry, 3 000 cavalry
Narrow Sea: 4 600 infantry, 400 light cavalry
TOTAL: 62 250 troops (16 600 infantry, 3 400 cavalry, 9 750 marines, 32 500 rowers)

Rowers would obviously not be taken to fight on land - they wouldn't fight even at sea unless absolutely necessary! Yet even ignoring the rowers, Stannis should still have had nearly 15 000 troops available.

And those 5 000 fighting men cannot include marines, unless we assume that either a) ALL men Stannis has are marines and he has absolutely no ground forces whatsoever, or b) Westerosi galleys have ridiculously low number of marines.

It seems clear that George Martin simply calculated numbers for land forces and then slapped on numbers of ships as an afterthought with no regard as to what that would mean for each kingdom's available fighting strength.

[Alden Rothack]

11 minutes ago, Aldarion said:

I had done estimates here:

https://warfantasy.wordpress.com/2023/11/09/military-of-westeros-1-organization-and-manpower/

Rowers would obviously not be taken to fight on land - they wouldn't fight even at sea unless absolutely necessary! Yet even ignoring the rowers, Stannis should still have had nearly 15 000 troops available.

And those 5 000 fighting men cannot include marines, unless we assume that either a) ALL men Stannis has are marines and he has absolutely no ground forces whatsoever, or b) Westerosi galleys have ridiculously low number of marines.

It seems clear that George Martin simply calculated numbers for land forces and then slapped on numbers of ships as an afterthought with no regard as to what that would mean for each kingdom's available fighting strength.

(Hi there, I'm a fan of the blog)

it would need to be both a) and b) for a fleet that large to only have 5000 fighting men

Honestly Martin seriously underestimates his numbers all over except for the iron islands which should either be much bigger, much more fertile or preferably both

 

 

 

 

 

 

 

 

[Aldarion]

1 hour ago, Alden Rothack said:

(Hi there, I'm a fan of the blog)

it would need to be both a) and b) for a fleet that large to only have 5000 fighting men

Honestly Martin seriously underestimates his numbers all over except for the iron islands which should either be much bigger, much more fertile or preferably both.

Thanks for following it!

And yeah, when I did population estimates for Westeros... turns out, realistic population of Iron Islands is lower than their likely military manpower. They literally have more soldiers than they should be able to have inhabitants on the islands!

[Alden Rothack]

12 minutes ago, Aldarion said:

Thanks for following it!

And yeah, when I did population estimates for Westeros... turns out, realistic population of Iron Islands is lower than their likely military manpower. They literally have more soldiers than they should be able to have inhabitants on the islands!

While the Iron islands probably aren't that thinly peopled as the Islands are closer to Orkney or Ulster than Norway

[Aldarion]

1 hour ago, Alden Rothack said:

While the Iron islands probably aren't that thinly peopled as the Islands are closer to Orkney or Ulster than Norway

Population density of medieval Ireland was cca 3,5- 9 people per km2 (70 273 km2, 630 000 in 1000 AD, 250 000 in 1500 AD).

England was 9,6 - 16,1 people per km2 (130 279 km2, 1 250 000 in 1000 AD, 2 100 000 in 1500 AD).

At 20 097 km2, Iron Islands can have a population of no more than 325 000. Even if we use France, which is pretty much the maximum likely density, we get the population of at most 1 000 000.

While that would make the manpower of Iron Islands possible, issue is that a) Iron Islands have been consistently described as sparse, rocky terrain and b) to have such a powerful fleet, Iron Islands would pretty much have to be covered in forests.

And having a) rocky terrain, b) extensive forests and c) large population all at the same time is pretty much impossible.

[Alester Florent]

Another thing to bear in mind is that Stannis is probably over-investing in ships at the start of ACoK in anticipation of more men joining him. He wants to pick up c.20,000 men from the Stormlands (and does) in addition to the ones he already has and wants to have the ships ready for their deployment immediately rather than having to recruit first and build afterwards.

[Alester Florent]

6 hours ago, Aldarion said:

And those 5 000 fighting men cannot include marines, unless we assume that either a) ALL men Stannis has are marines and he has absolutely no ground forces whatsoever, or b) Westerosi galleys have ridiculously low number of marines.

My thinking (and hence why I said above the distinction doesn't really exist) is that in this context a marine is just a soldier who happens to be on a ship, and there is no meaningful differentiation between Stannis's "ground forces" and "marines" - he'll use his garrison troops and levies to man his ships, and the same men will disembark and besiege Storm's End or KL. This also seems to be how the Ironborn operate, and makes sense with what we know of fleet actions prior to the gunpowder era, which were usually essentially land battles at sea, the fighting contingents of such fleets (whether at Salamis, Actium, Sluys, Lepanto) being made up of regular soldiers. Even at Gravelines - a battle between galleon-type ships fought almost entirely at range with cannon, the Spanish fleet had a large number of regular soldiers on board.

Quote

It seems clear that George Martin simply calculated numbers for land forces and then slapped on numbers of ships as an afterthought with no regard as to what that would mean for each kingdom's available fighting strength.

I do think this is also likely, though.

Edit: It may be - indeed I think it's probable - that GRRM was basing his figures on a different type of battle and indeed galley from those we might think actually appropriate: more like the 20-50 "marines" per ship of antiquity than the 200-ish of Lepanto.

Even the largest ships of the fleet are often described as "dromonds" which, assuming cognate with historical dromons, are not the great galleys of the late medieval period and Renaissance but rather smaller vessels with a correspondingly smaller crew and combat contingent.

With 5,000 fighting men across 80 galleys (assuming the transports are intended principally for his Stormlands recruits), at an average of c.50 "marines" per ship (as at Actium) that's more than enough men to do the job, with some left over.

Then again, the descriptions we get of the ships in Stannis's and the royal fleet don't match that. Swordfish and Lord Steffon, which may be among the larger ships in the fleet but not unusually so, have 200 oars, which is bigger in terms of oar capacity than historical dromons - and if there is more than one man per oar (as there should be) means a minimum oarsmen crew alone of 400. King Robert's Hammer is double that capacity... and the largest of Cersei's "dromonds" has 800 oars, considerably larger than even the biggest Venetian galleys of the early modern period, and one would expect a marine contingent in the hundreds for a ship that size. Confusion reigns.

Edited February 5 by Alester Florent

[Aldarion]

7 hours ago, Alester Florent said:

My thinking (and hence why I said above the distinction doesn't really exist) is that in this context a marine is just a soldier who happens to be on a ship, and there is no meaningful differentiation between Stannis's "ground forces" and "marines" - he'll use his garrison troops and levies to man his ships, and the same men will disembark and besiege Storm's End or KL. This also seems to be how the Ironborn operate, and makes sense with what we know of fleet actions prior to the gunpowder era, which were usually essentially land battles at sea, the fighting contingents of such fleets (whether at Salamis, Actium, Sluys, Lepanto) being made up of regular soldiers. Even at Gravelines - a battle between galleon-type ships fought almost entirely at range with cannon, the Spanish fleet had a large number of regular soldiers on board.

I do think this is also likely, though.

Edit: It may be - indeed I think it's probable - that GRRM was basing his figures on a different type of battle and indeed galley from those we might think actually appropriate: more like the 20-50 "marines" per ship of antiquity than the 200-ish of Lepanto.

Even the largest ships of the fleet are often described as "dromonds" which, assuming cognate with historical dromons, are not the great galleys of the late medieval period and Renaissance but rather smaller vessels with a correspondingly smaller crew and combat contingent.

With 5,000 fighting men across 80 galleys (assuming the transports are intended principally for his Stormlands recruits), at an average of c.50 "marines" per ship (as at Actium) that's more than enough men to do the job, with some left over.

Then again, the descriptions we get of the ships in Stannis's and the royal fleet don't match that. Swordfish and Lord Steffon, which may be among the larger ships in the fleet but not unusually so, have 200 oars, which is bigger in terms of oar capacity than historical dromons - and if there is more than one man per oar (as there should be) means a minimum oarsmen crew alone of 400. King Robert's Hammer is double that capacity... and the largest of Cersei's "dromonds" has 800 oars, considerably larger than even the biggest Venetian galleys of the early modern period, and one would expect a marine contingent in the hundreds for a ship that size. Confusion reigns.

Agreed, though my issue is not so much number of marines as it is number of rowers.

Rowers on warships are also soldiers - you cannot use civilians for that, because rowers from trade galleys simply wouldn't be capable of carrying out maneuvers that professional rowers can.

Large Byzantine dromond had 230 rowers and 70 marines. On Viking longships, rowers were marines as well.

So as I calculated for the Crownlands fleet:

https://warfantasy.wordpress.com/2023/11/09/military-of-westeros-1-organization-and-manpower/

Quote

Fury, Lord Stannis’ flagship, has 300 oars on three decks, deck covered with scorpions, and catapults fore and aft; the only galley in existence larger than Fury was King Robert’s Hammer, at 400 oars. Other galleys mostly had cca 200 oars. Ser Imry organized his fleet in ten lines of battle, each with twenty ships – normal galley tactics would have had one or two lines of battle, so this is likely a result of the constrained space. Additional 15 ships were lost along the way, so original fleet would have numbered 215 ships. It should be noted that this does not include Lyseni sellsails, which remained outside the bay as a rear guard. Ser Imry is noted to have had “four times as many ships as the boy king”, leaving Joffrey 50 ships. Original Royal Fleet would have thus numbered 265 ships. From example of Fury, and the fact that galleys have oars in multiples of 100, it can be assumed that one deck has 100 oars, or 50 rows. Byzantine dromond had 35 oarsmen on deck on either side and 25 beneath – 35 and 25 rows, respectively – at 32 meters length. As Westerosi galleys have covered decks, length of Westerosi galley might be 50 – 60 meters. Large Byzantine dromond had 230 rowers and 70 marines, and likely 170 oars. Out of 20 ships Davos lists, one has three hundred oars, two have two hundred oars, and 17 have a hundred oars. As Davos had noted nine particularly large galleys at Dragonstone, this disposition can be assumed to have been duplicated in all ten divisions. Assuming disposition similar to Byzantine dromond – two rowers per oar at third deck and one per oar at lower two decks, as well as soldiers as 30% of number of rowers – 300-hundred oar galley would have 400 rowers and 120 soldiers, 200-oar galley would have 200 rowers and 60 soldiers, and 100-oar galley would have 100 rowers and 30 soldiers. This is supported by the fact that Davos’ 100-oar galley is specifically noted to have had 100 rowers. Thus, each division of 20 ships would have had 2 500 rowers and 750 soldiers. Stannis’ fleet – 10 divisions – would have had 25 000 rowers and 7 500 soldiers. Original Crown fleet of 260 galleys would have had 32 500 rowers and 9 750 soldiers.

In short, Crownlands have to have a total of well over 60 000 troops to accomodate the fleet - and vast majority of them at sea. And this is similar for other kingdoms: full half of Westerlands' power ought to be taken up by the fleet, and nearly 30 000 out of Reach's 100 000 troops will be taken up by the fleet as well.

This does give a total of 400 000 soldiers for Westeros though, and is not completely impossible:

Quote

Ground troops: 244 500 (191 600 infantry, 52 900 cavalry)

North: 29 500 (22 500 infantry, 7 000 cavalry)

Riverlands: 20 000 (14 500 infantry, 5 500 cavalry)

Westerlands: 35 000 (28 000 infantry, 7 000 cavalry)

Crownlands: 20 000 (16 600 infantry, 3 400 cavalry)

Stormlands: 25 000 (20 000 infantry, 5 000 cavalry)

Reach: 65 000 (50 000 infantry, 15 000 cavalry)

Vale: 25 000 (20 000 infantry, 5 000 cavalry)

Dorne: 25 000 (20 000 infantry, 5 000 cavalry)

Naval force: 1 180 ships, 152 500 men

Crownlands: 260 ships, 42 250 men

Reach: 220 ships, 35 750 men

Westerlands: 200 ships, 32 500 men

Iron Islands: 500 ships, 42 000 men

TOTAL: 397 000 men

 

[Alden Rothack]

10 hours ago, Aldarion said:

Population density of medieval Ireland was cca 3,5- 9 people per km2 (70 273 km2, 630 000 in 1000 AD, 250 000 in 1500 AD).

England was 9,6 - 16,1 people per km2 (130 279 km2, 1 250 000 in 1000 AD, 2 100 000 in 1500 AD).

At 20 097 km2, Iron Islands can have a population of no more than 325 000. Even if we use France, which is pretty much the maximum likely density, we get the population of at most 1 000 000.

While that would make the manpower of Iron Islands possible, issue is that a) Iron Islands have been consistently described as sparse, rocky terrain and b) to have such a powerful fleet, Iron Islands would pretty much have to be covered in forests.

And having a) rocky terrain, b) extensive forests and c) large population all at the same time is pretty much impossible.

I think some of your numbers are off, though not by enough that its particularly plausible that the Iron Islands could continue to field such forces after the recent destruction of their fleet during the Greyjoy Rebellion

9 hours ago, Alester Florent said:

My thinking (and hence why I said above the distinction doesn't really exist) is that in this context a marine is just a soldier who happens to be on a ship, and there is no meaningful differentiation between Stannis's "ground forces" and "marines" - he'll use his garrison troops and levies to man his ships, and the same men will disembark and besiege Storm's End or KL. This also seems to be how the Ironborn operate, and makes sense with what we know of fleet actions prior to the gunpowder era, which were usually essentially land battles at sea, the fighting contingents of such fleets (whether at Salamis, Actium, Sluys, Lepanto) being made up of regular soldiers. Even at Gravelines - a battle between galleon-type ships fought almost entirely at range with cannon, the Spanish fleet had a large number of regular soldiers on board.

they had regular troops in addition to the available marines because they didn't have enough marines for the particularly massive battles involved

 

I do think this is also likely, though.

Edit: It may be - indeed I think it's probable - that GRRM was basing his figures on a different type of battle and indeed galley from those we might think actually appropriate: more like the 20-50 "marines" per ship of antiquity than the 200-ish of Lepanto.

Even the largest ships of the fleet are often described as "dromonds" which, assuming cognate with historical dromons, are not the great galleys of the late medieval period and Renaissance but rather smaller vessels with a correspondingly smaller crew and combat contingent.

With 5,000 fighting men across 80 galleys (assuming the transports are intended principally for his Stormlands recruits), at an average of c.50 "marines" per ship (as at Actium) that's more than enough men to do the job, with some left over.

the average at Actium was 120 per roman records

Then again, the descriptions we get of the ships in Stannis's and the royal fleet don't match that. Swordfish and Lord Steffon, which may be among the larger ships in the fleet but not unusually so, have 200 oars, which is bigger in terms of oar capacity than historical dromons - and if there is more than one man per oar (as there should be) means a minimum oarsmen crew alone of 400. King Robert's Hammer is double that capacity... and the largest of Cersei's "dromonds" has 800 oars, considerably larger than even the biggest Venetian galleys of the early modern period, and one would expect a marine contingent in the hundreds for a ship that size. Confusion reigns.

Actually one of the more reasonable takes on roman era war galleys would put the standard war galley as around the size of King Roberts hammer with the largest ever built (the forty) having 7000 marines on board,

they are bigger than the venetian average because venice was a trading fleet first and secondly because venice was only so big, they invested massively just to crew the ones they had.

1 hour ago, Aldarion said:

Agreed, though my issue is not so much number of marines as it is number of rowers.

Rowers on warships are also soldiers - you cannot use civilians for that, because rowers from trade galleys simply wouldn't be capable of carrying out maneuvers that professional rowers can.

Large Byzantine dromond had 230 rowers and 70 marines. On Viking longships, rowers were marines as well.

So as I calculated for the Crownlands fleet:

https://warfantasy.wordpress.com/2023/11/09/military-of-westeros-1-organization-and-manpower/

In short, Crownlands have to have a total of well over 60 000 troops to accomodate the fleet - and vast majority of them at sea. And this is similar for other kingdoms: full half of Westerlands' power ought to be taken up by the fleet, and nearly 30 000 out of Reach's 100 000 troops will be taken up by the fleet as well.

This does give a total of 400 000 soldiers for Westeros though, and is not completely impossible:

 

I suspect they do which is itself the reason why the lords of Westeros seemingly have so few soldiers for their populations, apart from the Iron Islands which is heavily over invested in its fleet the others have half or more of their strength in their navies and what we see is what they invest in their land forces, this resolves a number of issues IMO such as the Hightowers having the largest army but the Redwynes having the largest fleet, Manderly and his fleet etc

 

[Alester Florent]

If the "forty" was actually ever built, it wasn't a practical warship, and the 7000 crew figure would still include both rowers and marines.

[Alden Rothack]

9 minutes ago, Alester Florent said:

If the "forty" was actually ever built, it wasn't a practical warship, and the 7000 crew figure would still include both rowers and marines.

There was enough people who thought it would float that we know about it

even the largest war galleys in westeros are tiny by comparison, closer to what the venetians used than roman at its height though both both dedicated marine forces at least in terms of being specifically trained to fight at sea.

the ironborn would be unusual in not having separate rowers and marines, on a longship they is nowhere to put them.

[astarkchoice]

Well a fee things we forget.

Stanis fleet is most of the royal fleet which would normaly be around dragonstone, that and stannis commanding them during the ironborn rebellion is probably why he has command of so many of them. By blackwater he has 60-70  of the royal fleet joff has about 40. Stannis suplements this by hiring pre war  40 myrish sellsails and of course later gets  sallador saans fleet of 25 with a.mix of payment and the charm of his right hand (pun intended) man 

 

As for the ironborns population its perfectly plausible. For starters they are on the decline stage of their civilisation where once we know they held all the riverlands and north west coast and more so once would have had a larger population. We know they are right beside one of  westeros major trading and population centres in lannisport and despite the greyjoy motto they do trade extensively but unlike real vikings dont have to go very far. 

Unlike real vikings who if i recall had well developed laws even for women the ironborn can take a few saltwives on top of a rockwife  thus boosting their numbers of kids.

Also for  wood they probably trade (lannisports nearby mines would need  regualar timber too)  and/or chop down a few dozen here and there from their neightbours(the north)  massive forrests , the sheer scale of the north coast and jts massive forrrsts means they could do that occasionaly without notice.

[Alden Rothack]

19 hours ago, astarkchoice said:

Well a fee things we forget.

Stanis fleet is most of the royal fleet which would normaly be around dragonstone, that and stannis commanding them during the ironborn rebellion is probably why he has command of so many of them. By blackwater he has 60-70  of the royal fleet joff has about 40. Stannis suplements this by hiring pre war  40 myrish sellsails and of course later gets  sallador saans fleet of 25 with a.mix of payment and the charm of his right hand (pun intended) man 

Stannis has 80 war galleys and 80 transports plus the sellsails, at the least the war galleys would have to be his own pre-war ships, probably half to two thirds of the transports too.

 

As for the ironborns population its perfectly plausible. For starters they are on the decline stage of their civilisation where once we know they held all the riverlands and north west coast and more so once would have had a larger population. We know they are right beside one of  westeros major trading and population centres in lannisport and despite the greyjoy motto they do trade extensively but unlike real vikings dont have to go very far. 

unlike the real norse they also have superpowerful nations with a grudge and their own navies right next door

Unlike real vikings who if i recall had well developed laws even for women the ironborn can take a few saltwives on top of a rockwife  thus boosting their numbers of kids.

the norse had slavery the same as everyone else during the early middle ages, carrying off free women on the other hand was a good way to get an axe to the face, often from the women herself.

Also for  wood they probably trade (lannisports nearby mines would need  regualar timber too)  and/or chop down a few dozen here and there from their neightbours(the north)  massive forrests , the sheer scale of the north coast and jts massive forrrsts means they could do that occasionaly without notice.

even in the north you couldn't secretly cut enough lumber to build hundreds of longships.

[astarkchoice]

3 hours ago, Alden Rothack said:

even in the north you couldn't secretly cut enough lumber to build hundreds of longships.

Tru  but  taking a few sneaky huge redwoods/oaks cant hurt. Most of their wood  would be from lannisport(mines will need loads of timber as will  their fleet) arbour and the free cities.

[Alden Rothack]

19 hours ago, astarkchoice said:

Tru  but  taking a few sneaky huge redwoods/oaks cant hurt. Most of their wood  would be from lannisport(mines will need loads of timber as will  their fleet) arbour and the free cities.

the arbour is likely importing wood not exporting it

besides if they were willing to pay for the wood the north would sell it to them, its just they aren't