The Civil War was fought in over 1,000 locations across the country. The big ones that almost everyone knows are Gettysburg, Antietam, Shiloh, Vicksburg, etc. But the war was also fought in smaller places like Olustee in Florida, or Glorieta Pass way out in New Mexico. No matter where the armies moved or where the battle was fought, one thing was a constant – beside the soldiers, of course – and that was the terrain.
Terrain is defined as a geographical area or stretch of land with physical features that make it distinct. This means anything from creeks, rivers, mountains, ridges, fields, forests, and etc. We enjoy these places today through parks and other outdoor activities, but during the Civil War, terrain played a major role in how battles were fought and sometimes determined outcomes. Disasters, mishaps, reversals, and victories can be sometimes be blamed on the topography of the battlefield.
To start off, let me explain a little about what happens leading up to an engagement. Armies and divisions numbering into the thousands, or ten thousands, were moving across the country, either defending their land, or trying to take it from the enemy. Generals in charge of these armies sent out scouts, often cavalry for convenience of speed and maneuverability, to get the lay of the land. They’re looking for several things that will either help or hinder their objective in the coming battle. This was done if no reliable maps of the area were readily available. Some armies would employ map makers or topographers to draw out the terrain for them, making it easier to plan where exactly they wanted to put their men and artillery units.
One acronym to keep in mind is COCOA.
C – Critical Terrain
Critical terrain is terrain that gives the army a distinct advantage over a battle. There’s the popular saying that if one has the advantage over a situation, they have the “high ground” and in the Civil War, this was true. Height and elevation in the form of hills and ridges can allow for a number of things.
Positioning cannons and artillery units on a high ground affords them longer range. They can take aim on an opponent who is on lower ground and it is likely that they will not be able to fire back. Cannons can only be raised by so many degrees and if the only viable target within their range is the side of a cliff or a steep, slopping hill, their artillery is practically useless.
Infantry, likewise, have an advantage when occupying the high ground. If they are positioned on a hill, this gives them the same extended range like the artillery, but unlike the artillery units, their immediate problem lies with the opposing infantry charging at them. If they are on the high ground, especially if it’s steep and difficult to navigate, soldiers who try to take that hill are going to have a hard time doing it. As we all know, running up a hill can take a lot out of you. Imagine trying to run up that hill and firing a rifle, all while being shot at. I might add that the soldiers who are shooting DOWN on an enemy have a greater likelihood of getting a clean headshot on the enemy.
An example of this is in the assault made famous by the movie Gettysburg, where Colonel Joshua Lawrence Chamberlain and his men are defending Little Round Top against Confederate soldiers charging up the hill. They were able to hold this position because the Alabamians and Texans running up that hill were slowed down by the incline, the trees, and the bullets that the Maine soldiers were raining down on them. When it came time for them to fix bayonets and charge down the hill, Chamberlain’s boys didn’t have to use so much energy because it was on a downhill grade. I’ve personally been to Little Round Top, and though I’m not in the best shape, it was a rough hike. The Union occupation of places like Little Round Top at Gettysburg is a great example of having a piece of critical terrain.
O – Observation/Fields of Fire
While the battles are being fought, generals and commanders need to have a clear line of sight into the engagement. This means that, while the scouts are looking for ideal land for the army to fight on, they’re also looking for a place where the commander can set up their staff and direct the battle. This could be from a secluded point behind the lines that allows for cover, putting the commander out of danger. From these vantage points, commanders can be free to do what they do best and utilize their leadership skills.
Of course, a general can’t be everywhere at one time and there are limitations to this rule. This is why couriers and staff officers are important to the smooth execution of an engagement. Where the terrain impedes a general’s ability to observe the entire battle, a courier can carry news, whether good or bad, to the general from the other side of the battlefield. OR, you can be like General Robert E. Lee or Albert Sidney Johnston and roam up and down the battle lines, making changes and adjustments as deemed necessary. However, they need a safe path to travel in order to do this, which again, falls on the scouts to figure out.
The infantry, likewise, need to be able to fire their rifles without anything obscuring their view of the field or their enemy. It’s been said that many soldiers really didn’t have a huge range of visibility during a battle. They didn’t know what was going on beyond what their regiment or brigade were doing. However, it was absolutely vital that wherever they were firing, they could at least get a clear shot toward the enemy, either in a charge or when shooting their guns. This leads into the next point in the acronym.
C – Cover/Concealment
When we think of older battlefields and battle formations, the image of soldiers in neatly ordered lines across an expansive field comes to mind. While this was true for many battles, especially during the Revolutionary and Civil War, it wasn’t always the case. Yes, soldiers needed to be able to see and meet their enemy head-on, but they didn’t have a death wish. Some of us with no military experience whatsoever would say that marching across an open field like this is lunacy, but sometimes the commanders had no choice when it came to strategically overtake an enemy.
In other cases when soldiers were forced to fight in other circumstances, cover and concealment was just as important as having enough ammunition. A soldier needs to duck behind something to avoid a sheet of musket fire, and they need time to load their weapons after each shot. Cover and concealment go hand-in-hand because they can serve for the same purpose. There are many, many different forms of these.
Let’s just take trees as a first example. They can be helpful, especially if the trunk has a wide enough girth, because a soldier can duck behind these trees to reload and then turn to fire from a relatively safe place. An example of this is the West Woods at Antietam. While the trees there are rather skinny, they can still allow for a good deal of cover. I believe, along with other factors, that this played a big factor in the Confederate repulsion of the Union advance around the Dunker Church on that September 1862 morning. Trees, however, can have a downside. They may give too MUCH cover, rather indirectly. Where there are a lot of trees, there’s a lot of shade. Where there’s shade, there’s a canopy. What a canopy of trees and branches can do is trap the smoke created by the rifle fire, and fog up their field of vision. At Chickamauga, soldiers later said that they could barely see a yard ahead of them because the dense forest around them kept the smoke from clearing after a volley was fired.
Rocks and boulders could also be a great place for cover and concealment for obvious reasons. Snipers and infantry could use these natural rock formations to fire from, all the while tripping up their enemy. Devil’s Den at Gettysburg was a hotbed of fighting and target of conquest for the Confederate soldiers, because they understood the strategic advantage they would have in taking those rocks. John Bell Hood lost an arm trying to press his men forward around Devil’s Den.
Cover and concealment can also be found in manmade structures like fences or fortifications. If you could have walked through 19th century farmland, you would probably see a variety of different fences that penned in (or out) livestock and intruders. The most common that you’ll see on a battlefield park may be the Virginia Worm Fence. That’s the zig-zag stacking of split rails that were around 10-12 feet long. These weren’t the best cover, since they have the gaps, but those gaps could serve as ideal rifle slots to shoot through. A variation of the worm fence was the Stake and Rider fence. The modification involved planting stakes and adding an extra few feet to the worm fence that would 
deter any horses to vault over the fencing. Again, these were good obstacles and places for cover, since cavalry were unlikely to charge your line.
Post and Rail fence along the Sunken Road (Bloody Lane) at Antietam
Another popular fence was the Post and Rail fence, which was harder to deconstruct and typically lasted longer. The fence along Emmittsburg Road at Gettysburg is a good model for the Post and Rail fence. And then, of course, is the classic stone wall. These were perfect for cover and concealment because you were less likely to get shot by a lucky bullet when you duck to reload. Marye’s Heights at Fredericksburg is a beautiful example of this, where Confederates were able to repel Union charge after Union charge against their lines, because they had the perfect cover.
A less common fence was the white picket fence around a homestead that might not be a huge concern for the soldiers who fought in the fields, but they could be useful for the generals who set up their headquarters in the houses which these white picket fences guarded.
Buildings can be an awesome source of cover and concealment. At the battle over Fredericksburg was one of the first examples of urban battle in military history. Homes, shops, and barns can all serve as places for soldiers to duck behind or shoot from during the course of a battle. They can also become great places for headquarter setups or army hospitals. If a battle was fought on a farm, the family house could be commandeered by the soldier or commanders for these purposes.
If there was no cover or concealment, whether natural or preexisting, soldiers and army engineers would have to build their own. This is where forts and earthworks come into play. They would make these out of just about anything they could get their hands on. Trenches were dug around Vicksburg and Petersburg during the sieges to take cover while the Union assaulted Confederate fortifications. Trees would be cut down to strengthen breastworks around Atlanta when Sherman began his epic march to the sea through Georgia. In Yorktown, Virginia cotton bales were stacked to help give the soldiers the cover and protection they needed.
Forts would be built, mounding up long walls of earth in a few different styles. There were Lunettes, which were crescent moon shaped earthworks ideal for artillery pieces to fire from. This gave the team of men who were firing the cannons some cover while they loaded and reloaded. Believe it or not, artillery units were targeted just as much as the infantry. Redans were similar to Lunettes, but were typically more triangular and had an open side that allowed for the easy movement of troops in and out. A nice example of a Redan is the Third Louisiana Redan at Vicksburg that the Union tried to blow up with mines. A Redoubt is a Redan, but closed in on four sides and more resembles a real fort where soldiers would take shelter in during the battle or siege. Again, I refer to Vicksburg as a great place to observe Redoubts.
O – Obstacles
While all of these things can seriously help out an army, they can also be a detriment to the other. Just like fences can serve as cover for the Confederates on Bloody Lane during the battle at Antietam, they’re a big roadblock for the Union who were trying to press through that part of the battlefield. Trees that can provide concealment, can also spell disaster for an advancing brigade. Think about the Impenetrable Thicket and Hornet’s Nest at Shiloh, which kept the Confederates from achieving their objective in pushing back the Union left flank to steer them away from the Tennessee River.
Other obstacles that I haven’t mentioned, but are just as annoying as rocks and trees, are rivers and creeks. Again, you’ve got a double-edged sword. A water source is important for any army, whether at an engagement or while on the move. A soldier who is marching, and therefore sweating, runs the risk of dehydration if they don’t have an ample water supply. It sounds simple and kind of like a “duh!” moment, but this actually played into the success of the armies during the Kentucky Campaign early in the war. The state was in the midst of a bad drought and this slowed down the army’s movement, cutting back their daily progress almost a mile every day because the army was become dehydrated. Making sure that the army has a good source of water before and after the battle, especially if they plan on being there a while, like in the case of a siege, is something that scouts and generals are going to care about. Stagnant water like ponds and lakes can be a breeding ground for disease, especially if the uninformed soldier craps in the same place he fills his canteen. This is how dysentery spreads. Disease could be blamed for a large percentage of the casualties during the entirety of the war. Therefore, it pays to be picky about your water source. Go with flowing water every time.
At the same time, these rivers, lakes, streams, creeks, etc. can become an obstacle, not only to the enemy army, but to themselves. Depending on the depth of the creek and its width, it may not be crossable. And even if there’s a bridge, this doesn’t make it any easier. Antietam Creek was no picnic for Burnside and his men as they tried to cross over into the Confederate right flank. They tried sending men over the bridge (which was later named after the Union commander), but it became something of a killing zone. Men who tried to cross the river drowned or were easily picked off in the process. In other scenarios, even if the creeks or rivers are totally traversable, like the ones at Shiloh or Chickamauga, they can still slow a movement down.
Ridges and mountain ranges can completely derail an attack or campaign entirely as armies try to navigate around each other. Chickamauga might have been a Confederate victory, but they effectively pushed the Union army back in Chattanooga (which was the Confederate objective) and took the high ground at Lookout Mountain and Missionary Ridge. While Braxton Bragg now had the high ground, this meant that the Union would have to employ some miracle attack to take those two ridges and open up the way into Georgia.
Sometimes, the complete absence of anything on a battlefield can be a daunting obstacle. Remember that picture of long, orderly battle formations across an open field? Yes, open fields can be just as scary and insurmountable as ridges or mountains. Pickett’s Charge, in my humble opinion, was probably one of the gutsiest moves of the entire war. Longstreet’s division was ordered to march across a mile of open field after the longest artillery barrage in history up to that time, all in marching order and at such a pace that would make you bite your nails down to the quick. Watching the movie Gettysburg as the commanders such as Pettigrew, Anderson, Pickett, Armistead, and Kemper storm the field, my heart gets to pounding because I know – and they know – it’s a risky endeavor that did NOT turn out well. They didn’t have cover they needed so they’re getting hammered by artillery and infantry who aren’t even moving.
A – Avenues of Advance/Supplies
When you watch documentaries or see maps of the military movements during a battle or campaign, they’re shown as little red or blue bars moving across the screen. It’s way more complicated than that. An army runs on its stomach. This means, the men need food and supplies. Though the soldiers have haversacks and knapsacks, they can’t carry everything on their backs. Food, ammunition, tents, and other supplies are needed to keep the operation going. This means they need pack animals like horses and mules to carry everything. Okay, that problem is solved, but then you have to feed the animals. So, you’re not only carrying the food for the men, but also the food for the animals. Not to mention moving the artillery, which takes four to six horses to pull just one cannon. When a battery consists of four to six or eight cannons, that’s a lot of horses. That equates to a very, VERY long supply line.
Scouts are not just looking for the best ground to fight on, but they’re looking for good routes to take the army. Whether that’s through town, along trade roads, or finding a good railroad station that can move out supplies and men at a moment’s notice. It’s said that during the siege at Petersburg, Grant’s supply line and army, when lined up on a road just wide enough for the wagons and maybe 3-4 men to walk abreast of one another, it would have stretched for 64 miles. That’s about an hour’s drive down the interstate (if you go the speed limit).
Once an army is encamped and all their supplies are settled, routes from the camp to the point of battle have to also be determined. The artillery needs to be brought up in short order, along with the caissons that hold the ammunition. Likewise, paths for couriers, messengers, and reinforcements need to be established. Then, what happens if your army wins the field? You need to be able to move your army forward to enforce the enemy’s retreat or to take your target as you intended. The movement of the armies before and after the battle are just as important as when the guns are firing.
Another thing to keep in mind while assessing a battlefield and all these lovely points, is something that few things about. What time of the year is it? What’s the weather like? Is it raining? Snowing? What if it’s crazy hot?
These factors affected the terrain. If the ground was frozen, like it was during the siege of Knoxville, this will create problems for the army. They wouldn’t be able to easily dig to make fortifications, and like the Confederates discovered when they tried to take a fort, the ground can be too slippery to traverse. Cold can also mean disease and frostbite. Men who didn’t have good cover or shelter could freeze to death.
Likewise, if it’s really hot, dehydration – again – is a problem. They’ll sweat more, meaning they need to drink more. In the deep south, this sort of thing is obvious, but that may not be in the forefront of a Pennsylvanian’s mind. This is where supply trains are important to figure out, as well as a water source.
Raining, especially heavy rain, can play its own role. Rivers and creeks would swell, and the creek that you could wade through in September, is now swollen up to your chest in May or April. Roads were not paved back then, unless you were in a big city, so rain means mud. Mud means slower marches and delays in movements. It can also create unstable ground for armies to charge across.
Something that goes hand in hand with heat and rain are those pesky little mosquitoes that carry diseases. This was a big problem during the Vicksburg siege in July of 1863. The Mississippi, which was impassable because of Yankee gunboats, was a haven for mosquitos who bit the soldiers and made them sick with malaria.
It’s a lot for a general to think about when he approaches a battle, and if all of these factors aren’t taken into consideration, or ignored somehow, it can really mean victory or defeat for his army. They didn’t have GPS or radar or any form of reconnaissance technology to help him. Scouts, mapmakers, and locals are his best bet.
My challenge to you, if you should ever go to a National Battlefield Park that has been faithfully restored to its former state, think about these things. Go try to climb up the Third Louisiana Redan at Vicksburg, sit on the stone wall at Marye’s Heights in Fredericksburg, marvel at Devil’s Den at Gettysburg, and take a walk through the West Woods at Antietam. Walk in the footsteps of these soldiers and see what they saw. It’ll give you some interesting perspectives into the battle and the war as a whole.
Belle on the Battlefield 