Battle of Helm's Deep

In the movie, Helm’s Deep is manned by 300 poorly trained and equipped men from Rohan and 200 Elves. The elves are essentially the best trained and equipped of any fighting force in Lord of the Rings. Against them was a force of 10,000 Uruk Hai. Now, they were no match for the elves in terms of arms or training, they beat what amounts to the human rabble. The book kept the 10,000 uruks but there was 2,000 Rohan infantry and 1,000 cavalry. No elves were present.   So, what numbers would we actually see if my changes are made? Well, the main group retreating to Helm's Deep would be the Royal Family and the residents of Edoras. Which means the main fighting force from Rohan would the 120 Royal Guard. I suspect that the 4 companies that reinforce the Fords of Isen would be from the Royal Guard sent to garrison Helm's Deep. Which means that 720 riders would be in Helm's Deep until the arrival of the force from the Fords of Isen. Which means a total of 840.   Then there are the allies. Lothlorien would send help like it did in the movies. With the organizational structure I see the elves using, I suspect that 8 platoons for a total of 240 elves would be sent. The rest of their forces would likely be mobilized to attack Isengard or for home defense.   Then there is Moria. Moria's main issue here is speed. It would need more time to get all its troops mobilized. Plus, moving its entire force to Helm's Deep would be a bit difficult due to the extra distance and slowness of heavy infantry marching on foot.   So I think two things would happen. First, the second the discovery of Isengard's subversion and likely invasion, a battalion would be mobilized and sent to Rohan as soon as possible. Then, the rest of the army would be mobilized and sent after it had time to fully form up. To refresh ourselves here, this battalion would be 60 dwarves light infantry, 250 pike or spear men and 300 troops with crossbows.   This gives us a total force of 240 elves and 610 dwarves. Rohan would have 120 infantry and another 720 riders. Now, the question becomes how would these forces be deployed inside Helm's Deep? Most obviously, the riders would be converted to infantry and placed on the walls. Most likely, this would be in the Hornburg and the two layers of walls closest to the keep. Basically, you would want your Royal Guard in the most sensitive areas near where Theoden would be. The dwarves with slings would probably be put nearest the gatehouses due to the range issues. The crossbows would be on the two Hornburg walls. Ideally, the Deeping Wall would be where the elves would stand, as this would allow for the best exploitation of their extra range. The pikes would be inside the gates and the courtyards to deal with troops breaking in.   Isengard’s forces are superior primarily in their numbers and raw strength. Saruman is also presented as essentially an industrial powerhouse, producing large amounts of war material, including the first bombs in Middle Earth. Thus, it is presented as the industrial might of the attackers make the battle a foregone conclusion in their favor. Historically, well designed forts could actually hold out under similar conditions as what Helm’s Deep did – one castle actually could not be taken when the siege was 5 defenders to 100 attackers. So, why did Helm’s Deep appear to fall so easily?   Isengard would have two major advantages in its artillery barrages relative to World War One armies. The first is that by the time the Uruk-hai get close enough to actually attack, the defenders would already know it was coming. Thus, the problem of artillery telegraphing where and when the attack is coming would be negated already. Its not like Rohan was clueless. So the opening barrage did not have to be as well concealed beforehand. Then, there is the issue of the defenders knowing exactly when and where to send reinforcements prior. Both of these make the precision requirements of the artillery a little less strict.   In fact, the telegraphing issue might work in favor of Isengard. The impact of their surprise use in the Fords of Isen means that they would be effective terror weapons. Isengard could use the presence of cannons in his arsenal to scare the defenders. Simply letting them know the invading force had them would cause problems for the defenders even if no shots were fired.   Essentially, so long as the defenders remain suppressed and there are no friendly fire issues, the accuracy is good enough. They do not need to shoot far enough behind the fort to block reinforcements from arriving. Those are already in place regardless. Ultimately, taking Helm's Deep intact prior to the Rohirrim arriving - not artillery per se - is what is keeping that army alive. Supplies are also out of reach and Helm's Deep starts the battle with all it will get. So here too, one of the major problems of World War One artillery is made irrelevant.   This would influence his battle plan to a degree. The original attack plan called on the destruction of the main wall with a mine. This means Rohan would lose its main defensive advantage. But so too would Isengard after it took possession. Thus, I would imagine that cannons would be trained on the gates. Those would be much easier to replace. Attacks on the walls would be effective more as a diversion.   Lets say that the eagles decide to not attack before the invasion begins. What then? Well, the eagles would probably start by attacking the army in route to Helm’s Deep. The long, single column marching formations of the uruk hai would leave them quite vulnerable to eagle style bombing runs.

Should the army get to Helm’s Deep, 10 eagles would be all that is needed. They would be able to fly from behind the fort and skip bomb the army and dive bomb the ladders and ballistae. Should a hit occur on the mine the uruk hai had, Isengard’s main advantage would be gone. However unlikely, it is possible that the destruction of the mine could cause it to explode, killing a huge number of uruk hai in such a tightly packed army as Isengard’s in that battle. When the Rohirrim arrive, the uruks would do as they do in the actual battle and form a shield wall – making them sitting ducks for another skip attack. This would break up the uruk formation, making the Rohirrim charge even more devastating.   Lets look at the impacts of the Fords of Isen for a second. Once the main battle is lost, the Rohirrim would switch to their feigned and fighting retreat tactics. They would do everything they could to bait units into ambushes or away from the main column. That main column would be harassed with arrows as much as possible. Should a battery be exposed for long enough, it will be wiped out.   This would lead to a reduction in the overall size of the force Isengard has available. Some losses will occur. How many is of course difficult to determine. It also matters how many uruks are sent on pacification operations or to secure flanks. I will estimate that by the time the army arrives, it will be down to 15,000. This would be due to all three sources of casualties - Fords of Isen, battles in route and diversions.   It must be noted that this is significantly more lost than what Isengard lost in route in either book or movie version. Even with this, it still gives Isengard more forces available than in the canon versions. Again, this is based off numbers they had in the books and movies. Which suggests that the strategies are better on both sides than in the originals.   But these soldiers making it to Helm's Deep would be mainly the normal uruks in artillery, infantry and archers. The Wild Men and warg riders would have likely all been killed. The Fords of Isen would have been brutal to this force. Similarly, their diversions of Dunharrow and Edoras would have reduced those available for Helm's Deep further. Lastly, these would be the best suited for tracking down the harassing Rohirrim. So they would be the first of the Helm's Deep army to be wiped out. This would then force the use of less well suited troops for dealing with these attacks. Hence the losses would be higher.   The harassing Rohirrim would arrive at Helm's Deep just before the uruks. Their original force was a total of 1,800. But due to their losses, I suspect that functionally they would be down to probably 840. That would provide a decent numbers boost. And probably lead to haste on the part of the uruks. Annoyed by the constant low level losses and failure to defeat this force, they would be trying to deliver a death blow to them. Especially before they can hide behind the walls of Helm's Deep.   As they runs forward in a vain attempt to overtake on foot those on horse, they would be exposed to the Rohirrim already at Helm's Deep. The elves and dwarves would be perfectly set up to exploit the surrounding terrain to trap this advance uruk force and do massive damage. The result would be a lost opportunity to swift Uruk victory. Caution then would become the name of the game for them.   What would have happened if the changes to Helm's Deep and Isengard's military were made? First, a direct assault on the walls would have been futile at best and I doubt it would have been attempted. The other common option is to starve out the defenders. However, that would not work, as the successful delaying tactics is what allowed Gandalf and the Trees to arrive and save the battle for the defenders. The attackers did not have the time to erect good enough field works or have enough supplies to attempt to hold their position. Also problematic is the fact that the Glittering Caves could hold quite a bit of supplies. Plus, it is possible (though hard) to use the trails to bring in supplies if needed.   Far more likely to work and much more interesting than either the actual events of the movie or the ones I have explored so far is the last two options. The first is the use of chevauchée, a type of raid aimed at weakening a target primarily by burning and pillaging territory. It was used to either bleed an enemy, force an enemy to fight or discredit the targeted government so that the subjects are more likely to defect. This usually caused a massive flight of refugees to fortified towns and castles, which would be untouched by the chevauchée.   The second is treachery or deception. Both are common in sieges. In the 5 to 100 battle I mentioned earlier, the castle fell due to a trick when the assaults failed. Keep in mind that the attackers at Helm’s Deep had human allies from the area. Some of them might have known about the mountain passes into the back of Helm’s Deep and been able to infiltrate it.   Should these two be combined, it would have been powerful from a tactical and narrative perspective. The new strategy would require a splitting of the attacking force into two groups. The smaller group would be combined with the human allies to conduct the chevauchée operations. The second would attack Helm’s Deep – cutting off supplies and waiting.   The raiding force would attempt to burn down villages, loot, pillage and rape their way across the countryside. I'll say 5,000 are sent out for this just to get us down to the official numbers for the battle. This would have three effects – the first is scorched earth in that it denies the defenders possible supplies while granting them to the attackers. Then it would spread misery and terror in the minds of the defenders. Lastly, and possibly the most important, is it would bait the reinforcements into a field battle where Isengard would have the advantage. Should they still attempt to relieve the defenders in Helm’s Deep, the reinforcements would expose themselves to encirclement when the raiding force follows them and attacks from the rear.   Instead of wondering when Gandalf would have arrived, the question would be if he shows up at all. Meanwhile, the news of the raids would put pressure on the military commanders to sally forth to relieve the suffering of the civilians. After all, the reinforcements may not be out there doing it anymore. That debate would cause divisions and factions to emerge within the defender camp. The feelings of isolation, panic, stress and hopelessness would cause the already lower morale in the Rohan troops to strain even further. This would then cause fears about traitors to emerge on top of possible infiltrators, plus possible forms of racism turning the humans on the elves. Even if the defenders win, this would have resulted in a much better story to me.   The raider force would have most likely have been defeated in the long term. The Rohirrim would catch the Uruk Hai marching or in their camp at night, both times in which surprise attacks by heavily armed mounted troops are devastating. That would have taken the smaller force out of commission. Dealing with that force would still have slowed them down to the point that the siege force could operate on it own.   Honestly, how it happens is irrelevant. It seems unlikely that either Eomer or Gandalf would fall for the trap and let themselves get surrounded. Some form of pitched battle seems more likely on this front. Meaning that their arrival at Helm’s deep is much more likely to be either too late or in too small of numbers. The trees showed up too late to save the defenders – if Gandalf had not shown up, the defenders would still be dead.   This means that the siege force has a bit more time to work with, but not enough to go for full starvation. The use of noise and corpses would take place here, as well as the infiltration and subversion. There would likely then be a revolt and the enemy fifth column would ensure that the gates are opened.   This is where the surviving Rohirrim in Helm's Deep comes into play. The total of 1,680‬ riders would be useless inside the walls. But could be useful in dealing with the raiding force. Keep in mind the intentionally selective information that is getting through to those inside the walls. We know that Gandalf and Eomer are out there dealing with this force and would eventually get to Helm's Deep to provide aid. But those inside would just know about the uruk attacks. Probably with the decapitated remains of civilians being used to communicate that message.   So there would be powerful drives to unleash the riders to provide that aid. This would play to Rohan's strengths. But it would play to Isengard's too. After all, the valley would be filled with pike men and cannon. Sending out the relief force would likely result in them all getting killed. Many decision makers would recognize this. Hence the debates that would likely erupt - the very real and understandable desire to help versus the apparent low odds of it even reaching the intended beneficiaries.   Meanwhile, the besieging force simply has to make life inside the fort more difficult without actually assaulting the walls. This can be done most obviously through allowing reports to enter the fort regarding the actions of the raiders. Then there is the using catapults to fire corpses over the walls, a tactic we see Mordor use in Return of the King. Lastly, loud chanting and other stress inducing noises at all hours would be quite effective. We see that this is useful in demoralizing the defenders for the brief period it was used in the movie. Imagine how much more effective it would have been if used longer.   This would be where the cannons would shine. The batteries would set up and take aim behind the wall. The howitzers exploit their high trajectory to pull off this bombardment. This would drastically add to the power of the other forms of attack. Then, when everything is in place, the attackers would finally move in for the kill.   This time, the smaller guns would take aim at the gate seeking to blow it open with artillery fire. Then, some would move up under the protection of the archers and infantry so this can be repeated inside with the other gates. The medium guns would probably be used in suppressing fire and hurricane bombardments.   This is where the elves and dwarves would shine. The advancing troops would come under fire first from the elves. Granted, this would be much less due to the artillery fire. Then, the dwarves and Rohan's archers would start firing as the enemy gets closer. They would have much better support from the walls. Then, once the gate is breached, then the phalanxes of dwarves would essentially bog down the attackers.   The cannons moved up to blast the gates would be obvious targets for arrow fire. Their crews would probably be wiped out quickly. Which means that the battle would play to the defender's strengths at this point. The dwarves would be almost impossible to dislodge. Which means a huge force struggling to push into the gates while getting killed at the end of pikes.   There would be a massed group on the narrow ramp leading up the gate unable to contribute to the battle. Their attempts to fire inside at the phalanx would prove pointless. Dwarven armor would prove too strong on average. The volume of fire would probably be too low due to uruks blocking the archers behind them and the relatively small hole they have to hit. Meanwhile, they would be taking fire from those on the walls.   Huge losses would occur at this stage. The likely response from Isengard would be to move more small cannons up. Granted, this would be difficult due to that same arrow fire issue. But focusing the other guns on intense suppressing fire should make it possible. Then, no armor is good enough. Even if the dwarves are not killed outright by a massive shotgun blast, they would be knocked off their feet once the cannon is shot in. No phalanx is likely to reform fast enough. The uruks would exploit the opening and kill them.   But this is where the brilliance of the area between the two walls defending the Hornburg comes into play. The cannons are moved up to repeat this move at each gate until Helm's Deep falls. But this middle area would be a kill zone. A small number can pour fire into the opening once covered by the dwarves. Meanwhile the remaining dwarves would prepare to defend the second gate house.   Which means the uruks would be trapped in the courtyard. The uruks would need to get up on the outer wall and clear it of defenders in order to prevent them form shooting down on them. Simply taking the gate would not do this. Until the second gate house is cleared, they would be vulnerable to murderous fire. Huge numbers of ranged troops would be available to fire in. Which then means the attackers would be massacred.   Isengard's position would be tenuous at best. In the original book layout, the gates for the two walls protecting the keep were lined up. So theoretically, Isengard could actually shelter the cannon inside the outer gate to blast the inner one. But with the movie design, it is a bit trickier. They would need to move the cannons out into the courtyard. Then, two relatively cumbersome pivots would be needed to get them into position. The distances would be too small to get much speed going. Then, and only then can they prepare to fire. The entire time they are taking fire. So it seems like things would be rather hard at this point.   There was an interesting incident at the end of World War One. Basically the German Navy spent the entire war stuck in harbor. Their submarines took all the glory that was meant to go to the huge dreadnoughts every nation built as symbols of naval power and national pride. So when Germany in 1918 was clearly losing the war, the navy just had the inconclusive Battle of Jutland in 1916 and failed unrestricted submarine policy as their contribution. They felt that this was insulting and not reflective of what they felt was their rightful place in the war.   So the heads of the navy went rogue. They ordered a last ditch operation meant to throw everything they had at the British High Seas Fleet. The idea was one desperate attempt to break the British blockade, defeat them in open battle or go down in a blaze of glory. Ultimately this did more to provoke the mutiny that overthrew the Kaiser. But this was the plan at least.   Between the Royal Guard and survivors of the Fords of Isen, there should be 1,560 riders. In the military of a proud horse based military culture. A decent amount of them would be in the most prestigious unit in that military. Like the German Navy. Like the German blockade, the force raiding the surrounding area would be causing suffering for the civilians of Rohan. And these riders would see the battle in front of them slowly turning worse. And like a navy in a war defined by trench warfare, riders would not have a huge amount to contribute in the defense of a wall.   So it would make sense to me to see these riders decide to ride out on their own. Like the German Navy, they will hope to achieve glory through turning the tide. Or they will die honorably instead of dying like what they would see as like cowards if they don't act. They will be likely disillusioned with the leadership for keeping them bottled up. So this would be an expression of that divide I mentioned before in response to the raids. Some of the commanders might actually order this. Others will likely be against such insubordination. But these would either not know, be unable or unwilling to stop or get killed in the process.   Basically, all this to say that the charge we see in the movie would much more likely to be a rogue operation at the lower levels. But this would probably not go too well. Opening the gate to let them out risks letting in uruks. If they do get out right, the problems do not end. The same sharp turns that make it hard to get the cannons into position makes getting the needed speed for a charge.   The entire valley outside would know what was coming soon enough to form up pike ranks to stop the charge. Maybe not fast enough to stop major damage, but soon enough to stop the charges. Once that happens, it is a simple matter of using the cannons and missile units to massacre them. A rout or retreat would be forced after massive losses. Then the garrison would be forced to let their comdrades die before their eyes or open the gates. Opening the gates then yet again risks the uruks getting in too. Assaults in real life have won due to following garrison troops in as they retreat (or return after a swim). So this is a valid issue.   This is when the time issue starts to come into play for us. Essentially, the reinforcements of Gandalf would would need to show up now. Now, I think that Isengard would be brutal in their attacks. But methodical as well. This attack needs to succeed and Helm's Deep needs to be taken intact to retain its usefulness. Which means that caution would be the name of the game. The aggression demanded by Isengard's military doctrine exists to force decisive battles. Once that is assured, victory is what is more important. Which on one hand would demand an assault to prevent reinforcements or surprises. But one would also want to make sure that the decisive battle goes right. Once the enemy is trapped, it is stupid to take pointless risks that could allow them to escape.   All that to say that Isengard would probably exploit the time the raiding party buys the main force. But, the raiding force would be operating at a severe disadvantage. They would likely be found and defeated. The reinforcements might be later than they otherwise would have been. But they will show up. The result is an attack from behind. Which would catch the uruks between the charging Rohirrim and the wall - blocking their retreat and probably with some defenders still able to shoot arrows at them.

Would Helm’s Deep have fallen? Maybe. I know that the odds are much more in favor of Rohan. The only question in my mind is if Rohan’s morale cracks. There is no way to ensure that those will happen. Especially when one realizes that when faced with certain destruction, soldiers will rally and actually fight harder. The attempts to break the will of the Rohan soldiers might actually backfire. But with the changes to the fort, I suspect that this will be the only way it will fall.   The combination of revolt, fifth columns and surprise breach of the wall would make it extremely unlikely that Theoden and possibly Eowyn would survive. Theoden is a rather old man and would likely not be able to make it out. He might have protection from the Fellowship if he survives the initial attacks, but he will be slower and will likely get killed by an arrow as they flee through the Glittering Caves.   Aragorn, Legolas and Gimli are more likely to escape, as they are overpowered and the predicted death of Theoden would make them able to flee faster. Still, this is likely to be the closest these characters come to death outside of Moria. Or it is possible that one or all of the Fellowship characters could have been killed in their sleep by an ambush. This means that the political leadership of Rohan is mostly gone, along with its main fort.   But, the trees would still show up, cutting off the withdrawal of the besieging army, killing them. Isengard’s defeat would be total in this version as well, but not without significant damage to Rohan that will cripple its ability to come to the aid of Gondor. The death of Theoden and the reduction in force size by a defeat in either the pitched battle or the siege would have made Rohan weaker.

But there is always a catch. In order for the war between Rohan and Isengard to have been won at this stage, you would need Helm’s Deep to be a decisive battle of annihilation. But that would have not happened. Remember – Rohan was only nominally under royal authority. The Rohirrim numbered an estimated 12,000 in the books, and at most 3,000 of those would have been lost in Helm’s Deep. The result? 9,000 heavy cavalry in small groups under hyper local authority scattered over the rest of Rohan.   So, basically there is no hope of Isengard winning its Helm's Deep campaign. But that honestly is irrelevant. It is screwed no matter what happens. The destruction of the central government at Helm's Deep would fragment Rohan - not defeat it. After all Rohan's government hardly had much power and influence over the population. The result would be Isengard having to move its troops over the entire territory to defeat local resistance.   The problem is the one of dispersal verses concentration. Saruman would need to be able to conquer and hold the entire territory at the same time in order to deny the Rohirrim bases to operate, assuming that they are unable to get safe haven somewhere. Which is unlikely - providing safe haven would be extremely likely for Lothlorien and Gondor. Even in this worst case scenario where no outside aid is given, Isengard would still be greatly exposed to the sort of hit and run tactics that we see Éomer actually use against Isengard in the Two Towers.   Then there is the inevitable outcome of the defeat of Rohan. Any illusions about the threat Isengard faces will be lost. This and the ever present need for more resources would put Isengard on a collision course with Lothlorien - a natural target for its wood. Lothlorien would already be in a state of war with Isengard after the killing of its troops at Helm's Deep. Lothlorien presents the same problem that Rohan does. It would just use light infantry to wage guerrilla war instead of heavy cavalry. So even if Isengard is able to completely defeat and occupy Rohan, it still faces immediate and significant problems.   But the major benefits would be for Mordor itself. I suspect that Sauron would know just how screwed Saruman would be. But he would also not really care. Any attack by Isengard would be of value to Mordor. Fighting in Rohan would distract Rohan, Lothlorien, Moria, the Ents and eagles, possibly Mirkwood too. This would lead to both delays in reinforcements getting to Minas Tirith and reduction of their power even if Saruman loses. Plus, Saruman is of questionable loyalty, so his defeat would eliminate a potential future problem. So the worst case scenario would still be useful. Granted, it would be ideal for Isengard to totally defeat all these regional powers and send its army to Minas Tirith. But this is both highly unlikely and not needed for Isengard to be useful.   Now, without the Wizard Ring plan, things on a military front would be even worse for Isengard. By this point it would be clear that Isengard was a threat to Mordor. Which means that Mordor would use forces from Dol Guldor to eliminate this. The forces would already be in place in case problems from other powers arise.   So now Isengard would have ring wraiths and a large land army to deal with. That would not be good. Honestly, by this point I suspect that Isengard would be defeated by other forces. But I suspect that the forces mobilized to crush Isengard would 1) not be idle as another enemy army moves into the same area and 2) let Isengard fall into the hands of said enemy. Which means that Mordor's forces in Mirkwood would be attacked now.   Also important would be the impact on Minas Tirith. We know that it was the Army of the Dead that saved the day in that battle. But the garrison only survived as long as it did because of the Rohirrim arriving. That was only possible because Theoden survived to order that force deployed there. Thus, a victory at Helm’s Deep would have meant a victory at Minas Tirith. We can assume that this was the desired outcome Sauron hoped to get when he recruited Saruman.   But this then sees where Isengard could backfire on Mordor. Rohan would be required by treaty obligations to come to Gondor's aid, and by so doing would likely drag Moria in too. Moria would need to make sure Rohan survives. Mordor is clearly a bigger threat to its investments. Plus it was the puppet master behind the threat that justified its first mobilization. Add in the fact that Aragorn would be an important person involved in the resurrection of the kingdom of Moria and there is a powerful motive for Moria getting involved.   Then, Lothorien, the eagles and ents would be mobilized when they would not otherwise be. Even Rohan would not be ready to fight yet without the Helm's Deep campaign. Which then means that a powerful coalition would have materialized. One that is both more powerful and ready to fight sooner than Mordor was ready for or planning on. So Mordor's long term interests became endangered due to the desperation of Isengard too.   This not only means the loss of the Rohirrim – a very powerful mounted force – but also possibly the Army of the Dead if Aragorn is killed. This has potentially huge impacts by itself. As Minas Tirith would have fallen without the intervention of both these forces, even without the aid of Isengard, a victory at Helm’s Deep would have been devastating.   The loss of the Rohirrim would not be decisive by itself, as the battle would have been lost with just the Rohirrim and no additional help. They would have arrived and done major damage to the orcs, but the Easterlings and the ring wraiths would still have defeated the two armies of men. The Rohirrim allowed victory by delaying defeat until the army of the dead arrived. Should they not have arrived due to the death of Aragorn, Minas Tirith would have fallen. Should the Rohirrim not be a factor due to defeat at Helms Deep, but Aragorn survived, Minas Tirith would still have suffered horrible losses, but not irreversible ones. This stems from the fact that the Rohirrim slowed, but did not stop the breaching of the walls and the ransacking of part of the city. The breach would have taken place without their assistance, but would have continued unabated until Aragorn showed up.   However, at the level of grand strategy, a total defeat at Minas Tirith – which is much more likely in the case of a Helm’s Deep loss – would not be the end of all hope. As long as the Ring of Power still gets destroyed, the war is won for the good side. What remaining forces could still attempt the diversionary strike and Frodo could still drop the Ring into Mount Doom.