Union Antietam -- Enveloping Johnny Reb at the Sunken Road

[The Greg Machine]

Okay so, has anyone managed to completely envelope the confederates at Antietam? I managed to not only drive the rebs back all the way to the sunken road from the church, but also managed to cut them off from Sharpsburg. Once you receive reinforcements from the Southeast I crossed the river there and almost completed the encirclement, but the rookie brigades ended up crumpling under fire from the late confederate reinforcements.

Back up at the Eastern edge of Sharpsburg--which had been captured earlier and held at heavy cost to the union skirmishers due to three confederate artillery sections--my brigades were rounding the 3/4ths enveloped rebel army as fast as they could but kept get routed under the combined weight of most of Longstreet's corp and nearly all of Jackson's decimated, but already elite, corp--with elite elements from Longstreet throwing just enough bodies at my Union line sweeping up from behind to prevent it from bearing the full weight of its fire on the closely clustered confederate forces.

By the time I could finish the battle, there was only one lane about the width of 3 divisions between my main forces and the rookie reinforcements holding on in the southeast on the banks of the river, but the pocket was collapsing quickly and it didn't seem likely I would be able to complete the envelopment. I think part of the issue was my inability to make a real thrust from the initial diversionary attack and link up those brigades up with the main line--one section of artillery being lost and a brigade pretty badly decimated--with Lee making three or four aggressive counterattacks down the hill to the bridge crossing. The other part was, once my brigades rounding the partially enveloped main body of Lee's army began to wager, an unfortunate corner formed where close five confederate brigades could fire on two union ones.

There was still a chance I could build enough pressure at the back of Lee's retreating army to force them to stand and fight, but I gave up the envelopment once the confederate reinforcement line wedged itself between my main force and SE reinforcements and ended the battle, but I've played just past Fredericksburg and I have been thinking about it every battle since.



Anyone done it? Care to share your strategies and stories?

[Flharfh]

The two times I have played as Union I have had enough of a numerical advantage that I could just do frontal attacks and bash the rebel army. No need for anything fancy.

[Wrigley]

I was able to encircle them. Basically I went into battle with 3 corps: Grant's Corps (containing an entire division of 3 star elite brigades and 1 24-gun battery, equipped with Lorenz rifles and 24lb Howitzers), which was fully reinforced (army org was at 8 for reference). Sherman's Corps, mostly filled and with one star or rookie brigades, but with decent armament. Then McClellan's Corps, which consisted of a couple of understrength green divisions.

I set up Sherman's corps to assault the church, Grant's corps to attack the sunken road, and McClellan's corps to attack over the creek.

Sherman's assault was slow. I first took Nicodemus hill and pushed 3 brigades around through the woods, and basically sent waves at the church, along with 2 divisions towards sunken road but not to it, to flank the forces at the church. It was bloody and slow. Meanwhile, I crossed the river with the first wave of reinforcements, and took position on the rear slope of the hill next to the sunken road.

When Grant's corps arrived, I had them take up position in preparation for attack along the sunken road, and then push forward along with my flanking force on the hill. Sunken road fell within minutes.

Meanwhile I was able to put 4 brigades of McClellan's corps firing on the Confederates holding the bridge, and force a crossing. From there I sent 3 brigades south to watch for reinforcements, 2 brigades and a battery of Napoleons north to hold the ford to keep the rebels trapped, and 4 brigades into Sharpsburg itself. The Confederates had pulled brigades out of Sharpsburg to try and stall my assault from the north, so it was undefended in the town itself.

Once sunken road was taken, I used my flanking force to take up position on the north side of the stream, and used several of Grant's brigades to finally clear out the church. There was no room for all but 4 of Sherman's brigades now (which took position on the north side of Sharpsburg near the road), so I sent the rest of his corps south in time to meet the Confederate reinforcements along with the 5 brigades I had in place delaying them. The pocket complete and in no real danger of falling, I began to close it only to have the battle end because I took all the objectives! 20,000 rebels escaped to fight another day because the game mechanics.

Basically I'd say there were 4 main points to my success here:

1. Take Nicodemus Hill and bring brigades around. Without that taking the church will be incredibly bloody, and you can't put enough pressure on the Confederates to have them draw brigades from the south. Their reinforcements will go after this flanking force instead of reinforcing the church directly, and this is crucial.

2. Get the flanking force across the northern bridge as quickly as possible. You have a limited time before the Confederates react so get them across, but don't attack until your second Corps arrives. They aren't going to be enough to take the sunken road and hold the Confederates by themselves.

3. Take sunken road fast. This not only draws yet more Confederates from the south, but also speeds the fall of the church and frees up your first corps to march south to strengthen the pocket. Point 2 is very important if you want to take the sunken road with the speed necessary.

4. In the south get your forces across the bridge, put two brigades and a battery on the stream crossing (anything less and you might get overrun), and use the rest of the brigades to spread out and gain a foothold in Sharpsburg.

The sooner you free up your original corps, the sooner you get a secure pocket. Even if you have to fight through Sharpsburg, you can do that if you have a corps at your disposal. The third corps is essentially to block that south ford, contest Sharpsburg, and delay the Confederate reinforcements. You won't be secure until you get your first corps down there.

[The Greg Machine]

@Flhalfh, actually the envelopment was only made possible because I DID bash them. Case in point with my below response to Wrigley.

@Wrigley, I took Nicodermus hill quite easily and over the course of the assault on Dunker Church actually managed to lure Stuart's cavalry into a trap where they were completely destroyed. Unfortunately, that very action is probably what caused my envelopment to fail.

While most of my 1st divison successfully took Dunker's Church via a wheel maneuver which forced most of Jackson's Corp off the field, destroying J.E.B. Stuart's cavalry took up three brigades and several skirmisher units before the end of the first phase of the battle.

Next, as Dunker Church fell, Longstreet moved up most of his reserves which cost me more time, but was ill capitalized upon by the defenders of the sunken road, who refused to give up their defensive ground in support.

Gradually, both my now-rearguard brigades on Nicodermus hill and a section of artillery moved to the north of Sharpsburg, past the western-most edge of my main battle line, where they delayed more of Longstreet and Jackson's reinforcements while the bulk of my first corp and elements of my second approached the left-most side of the Sunken Road on a gradient.

Again, it was quite easy to roll up the rebel line at the sunken road, with the bulk of my second corp arriving to hold up any unengaged frontline troops hoping to reinforce the rebel left. This is where the real trouble for me began. While it was easy enough now for the initial diversionary attack to cross Middle Bridge, it was nearly impossible for the rookie brigades therein to make any progess up the hill towards Boonsboro Road--several elite divisions and a shockingly large portion of Lee's artillery making any assault impossible.

*though this posed no immediate threat to the overall wellbeing of the Union army on the field, it allowed for/caused several grievously broken rebel brigades to slip very far southwards.

Now the noose began to tighten. First, Longstreet's forces holding up the brigades from Nicodermus hill began to falter and retreat while most of the veteran--but highly depleted--brigades from Jackson's corp hung back and were loathe to engage several full stength (~2000 men, only 6 army org at this point in my campaign) union brigades with artillery support. Thus I detached two skirmishers units and redirected my dedicated sharpshooter unit to the capture of Sharpsburg proper where I had noticed several rebel supply wagons. I captured the city, one of the supply wagons, and managed to isolate three of Lee's artillery sections.

At this point, most of my forces had converged on Lee's army around an area confined by Sharpsburg, the Sunken Road, the small stream east of Sharpsburg, and Antietam Creek itself in a rough 'C' shape. The bulk of my army pushed East towards Antietam between the Sunken Road and just North of Sharpsburg with elements also holding strong along "Bloody Lane" itself. However, as I previously mentioned--Lee and Longstreet prevented my forces from Middle Bridge and my reinforcing 2nd corp sweeping Southeast from linking up by means of pretty extreme concentrated artillery fire and fierce counterattacks down the Eastward facing hills on the edge of the Sunken Road.

Meanwhile, I had little forces to dedicated to routing the rebel artillery now North of Sharpsburg and that remained a thorn in my side for the rest of the battle. With a superior force, I was easily able to begin routing Lee's forces, and initially I was able to stem their retreat at the stream east of Sharpsburg via a combination of veteran brigades and the forces from Nicodermus hill. However, I simply could not match the sheer weight of numbers Lee brought to bear on that side--my own reserves still marching around the lines of encirclement.

Next, my forces from Burnside's Bridge managed to get over the bridge in excellent order, initially moving to block A.P. Hill from reinforcing Lee. Unfortunately, this is when I began to notice that routing forces from the only partially-enveloped Lee were began to trickle out of the trap I had caught them in and reformed to attack my blocking force from behind. They were actually routed and I managed only to reform them to defend their bridgehead.

At this point, I had actually captured several of the rearguard brigades of Longstreet's corp and was coming up on the bulk of Lee's army when one of my veteran brigades broke after really heavy fire from vastly superior rebel forces before my reserves could round the line to spread the damages. Then gradually, the unholdable corner formed and the line could only reformed just East of Sharpsburg. The envelopment was practically foiled when most of Hills forces managed to get between Sharpsburg and Burnside's Bridge.

[The Greg Machine]

Overall, a seriosuly overwhelming victory with the Union getting better stats in every area, especially casualties inflicted--but I am still distraught that I could not destroy the bulk of the rebel army.

[Wrigley]

Where are you concentrating your best forces, as that may be a deciding factor? You can't just push the rebels out of the sunken lane, you need to push them into the fields beyond and then hold a strong line while transferring your first corps south.

Also, your forces crossing Burnside's bridge *cannot* ignore the ford to the north. Put at least a brigade on it.

Either way it sounds like you're moving too slowly. AP Hill's division had only just arrived on the field and engaged my line when the battle ended. You also sound like you have too many brigades "playing cleanup" with Stuart's cavalry and the like. Ideally you'll have a brigade or two blocking your Nicodemus Hill flanking force from being flanked itself, and a few skirmisher/cavalry units running around dealing with stray artillery, cavalry, and supply wagons. Additionally, are you concentrating your artillery or keeping it seperate? I put the entirety of my first and second corps/ artillery (a total of 196 guns) behind my forces along the sunken road, where they'll hold any attacks the Confederates make and decimate anyone that comes within range.

Again, it's about *quickly* freeing up that first corps and bringing it around south of Sharpsburg.

[The Greg Machine]

I had my 1st Corp assaulting Dunker Church, with my elite 1st Division in reserve. Throughout the course of the battle, I was never actually bogged down using only 1 and 2 star brigades on the battle line.


I managed to transfer the first of my elite brigades to the end of the partial envelopment fairly quickly. After that, they had to be used to prop up the line that had gradually shifted into attacking Lee from the rear instead of rounding the line and completing the envelopment completely at Antietam Creek. Even after that, I managed to shift a single reserve brigade all the way round to the end of the line, but my first elite brigade cracked before it could properly position itself--which again forced me to use more reserve brigades meant to continue further towards Antietam to prop up what line there was.


Artillery was mostly concentrated near the top of my battle line, but had one battery at both ends that were supporting various moves in those areas throughout the battle (out of maybe 5-6 batteries???) Definitely did not have 196 guns though, 144 max, probably closer to 100-120 at the time. My own cavalry (two deatchments of 250 men) was destroyed after routing three units of rebel artilley by Stuarts cavalry. I didn't move my forces too forward from Nicodermus until I had totally driven Stuart from the field--which caused the biggest delay imo.


Although, I have to admit, the Burnside's Bridge was an action I bungled fairly completely, only managing to distract A.P. Hill and Lee's hitherto routing forces (not the bulk, just those that had been broken badly and in some form pursued.)

[Wrigley]

Originally posted by The Greg Machine:

I had my 1st Corp assaulting Dunker Church, with my elite 1st Division in reserve. Throughout the course of the battle, I was never actually bogged down using only 1 and 2 star brigades on the battle line.


I managed to transfer the first of my elite brigades to the end of the partial envelopment fairly quickly. After that, they had to be used to prop up the line that had gradually shifted into attacking Lee from the rear instead of rounding the line and completing the envelopment completely at Antietam Creek. Even after that, I managed to shift a single reserve brigade all the way round to the end of the line, but my first elite brigade cracked before it could properly position itself--which again forced me to use more reserve brigades meant to continue further towards Antietam to prop up what line there was.


Artillery was mostly concentrated near the top of my battle line, but had one battery at both ends that were supporting various moves in those areas throughout the battle (out of maybe 5-6 batteries???) Definitely did not have 196 guns though, 144 max, probably closer to 100-120 at the time. My own cavalry (two deatchments of 250 men) was destroyed after routing three units of rebel artilley by Stuarts cavalry. I didn't move my forces too forward from Nicodermus until I had totally driven Stuart from the field--which caused the biggest delay imo.


Although, I have to admit, the Burnside's Bridge was an action I bungled fairly completely, only managing to distract A.P. Hill and Lee's hitherto routing forces (not the bulk, just those that had been broken badly and in some form pursued.)

Ok so first thing I noticed is that you need more cavalry. Its uses are extremely limited but you need it here. I had 3 detachments of 700 men with carbines, which allowd me to delay and harrass at will while my main forces closed the pocket.

You'll also want your best corps attacking the sunken road. This is because the geography makes it so your corps attacking the church is much closer to where you need to rush your brigades to complete the encirclement, and the best way to take out the rebels at the church is from the sunken road. Put your elite brigades there and flank thr church, then rush your brigades south.

Finally, don't attack Lee from the rear. You're not going to envelop the later AI reinforcements and ideally you'll envelop the rebels before Hill even arrives. You can "herd" Hood's division into the pocket but the others just prevent from linking up with the pocket itself.

Essentially focus on what you can accomplish. A single brigade can hold in Sharpsburg for a long time, so delay rebel reinforcements until your first corps can arrive, but again time is of the essence. Don't waste precious minutes chasing down artillery, cavalry, and skirmishers with your infantry. Bring more cavalry to do that.

[emcdunna]

I did this. I killed 80% of their entire army, once fully encircled, their triple star units got annihilated and broke and fled into my men. I chased them down with cavalry.

I did this with mostly 0 - 1 star infantry with M1842s. Use more units, not elites :)

Anyway i couldnt finish them off cuz their reinforcements showed up and the battle just ended prematurely

[J. P. Armistead]

I played as CSA on BG and held all VP'S .
Union concentrated on Dunker church but could not break my lines.
I strongly held the northern bridge and completely destroyed the forces trying to cross it so there was no pressure at all put on the sunken lane.
One lonely brigade sat there eating goober peas waiting for some action.
As the Union forces depleted themselves north and west of the Dunker church i withdrew some brigades to move to Sharpsburg.
I held burnside at the souther bridge with 3 brigades until my reinforcement from the sunken lane area and sharpsburg arrived. One two Union brigades crossed the northern bridge but i held them with a couple of brigades that were nearby. End of that threat.
Meanwhile 3 cavalry brigades and some detached skirmishers moved around the Unions exposed left flank and destroyed all their artillery batteries.
Battle over.
I lost 10K of my 32k army, Union lost 37k of their 57k army and 93 guns.
Note that i play with smaller armies( max brigade size 1500, artillery brigades12 guns) until later in the campaign.
This allows me to have more brigades for tactical flexibility.
On this occasion it sure paid of.

I'm sort of worried that the CSA campaign will be getting easy just as my Union campaign did since the patch that allowed depletion of enemy forces as the campaign progresses.

Last time i played Antietam i had a much harder time having to fight in the streets of Sharpsburg, and using the "trick" of retaking the Dunker church and Sunken lane just before the timer ran out.
This time i was not under any real threat at all.

[edwardstoner]

A very interesting and informative thread. Thanks to all of the contributors!

[emcdunna]

Originally posted by J. P. Armistead:

I played as CSA on BG and held all VP'S .
Union concentrated on Dunker church but could not break my lines.
I strongly held the northern bridge and completely destroyed the forces trying to cross it so there was no pressure at all put on the sunken lane.
One lonely brigade sat there eating goober peas waiting for some action.
As the Union forces depleted themselves north and west of the Dunker church i withdrew some brigades to move to Sharpsburg.
I held burnside at the souther bridge with 3 brigades until my reinforcement from the sunken lane area and sharpsburg arrived. One two Union brigades crossed the northern bridge but i held them with a couple of brigades that were nearby. End of that threat.
Meanwhile 3 cavalry brigades and some detached skirmishers moved around the Unions exposed left flank and destroyed all their artillery batteries.
Battle over.
I lost 10K of my 32k army, Union lost 37k of their 57k army and 93 guns.
Note that i play with smaller armies( max brigade size 1500, artillery brigades12 guns) until later in the campaign.
This allows me to have more brigades for tactical flexibility.
On this occasion it sure paid of.

I'm sort of worried that the CSA campaign will be getting easy just as my Union campaign did since the patch that allowed depletion of enemy forces as the campaign progresses.

Last time i played Antietam i had a much harder time having to fight in the streets of Sharpsburg, and using the "trick" of retaking the Dunker church and Sunken lane just before the timer ran out.
This time i was not under any real threat at all.

Just consider also that when you play the game the second time, you know a lot more about what will happen and what to do. It makes it easier to get a better result

If you want the enemy forces to re-build up, just try not slaughtering them at one of the battles. Fredericksburg features stupidly large forces from the union regardless of what you did (probably goes over the army recon number), so you dont need to worry for the next one.

[Loxodon Historian]

I have won Antietam twice as Union Regular difficulty with the same tactic: a big right hook. Avoid the cornfield, sweep over Nicodemus Hill, and swing into West Woods and Dunker Church from the west. This flanks the entire cornfield area with its multiple lines of defense. Watch your southern flank (Hood shows up). Keep shaking your line out southward toward Sharpsburg and you can flank the Sunken Road.

The first time I played Antietam as CSA the Union AI used the same tactic against me with success, although I managed to squeeze out a draw. The second time the AI for some reason attacked me headlong through the cornfield and got mauled, especially when I counterattacked from Nicodemus Hill.

[emcdunna]

Originally posted by Joshism:

I have won Antietam twice as Union Regular difficulty with the same tactic: a big right hook. Avoid the cornfield, sweep over Nicodemus Hill, and swing into West Woods and Dunker Church from the west. This flanks the entire cornfield area with its multiple lines of defense. Watch your southern flank (Hood shows up). Keep shaking your line out southward toward Sharpsburg and you can flank the Sunken Road.

The first time I played Antietam as CSA the Union AI used the same tactic against me with success, although I managed to squeeze out a draw. The second time the AI for some reason attacked me headlong through the cornfield and got mauled, especially when I counterattacked from Nicodemus Hill.

That's definitely the best early game tactic, but if you only send men to the flank, at some point the ai will pull forces away from the frontline that you ignored and attack you. The most effective way is to pin them from the front with cheap troops while your elites flank&spank them to a speedy defeat.

The earlier you beat them back from the objective, the easier it is to surround them later on and annihilate them completely.

[The Greg Machine]

I think it might actually be preferable to do just enough to actually hold them at the Sunken Road, that whole bluff kind of area around Boonsboro Road is the best place to surround them entirely I think. Otherwise you risk units slipping A.) Into Sharpsburg itself, which makes any sort of envelopment impossible, or B.) down towards Burnside's bridge. If you can really draw the Confederates into a pitched battle at "Bloody Lane" without getting caught in anything too viscious, get troops into Sharpsburg, and flank Lee while he's still engaged in his defensive positions, then you should be pretty set.

Everyone seems to be advocating beating them off the objective entirely, but it doesn't seem like you actually have that much space to work with. Sharpsburg is a fortress if either side gets an appreciable amount of defenders in it.

[emcdunna]

Originally posted by The Greg Machine:

I think it might actually be preferable to do just enough to actually hold them at the Sunken Road, that whole bluff kind of area around Boonsboro Road is the best place to surround them entirely I think. Otherwise you risk units slipping A.) Into Sharpsburg itself, which makes any sort of envelopment impossible, or B.) down towards Burnside's bridge. If you can really draw the Confederates into a pitched battle at "Bloody Lane" without getting caught in anything too viscious, get troops into Sharpsburg, and flank Lee while he's still engaged in his defensive positions, then you should be pretty set.

Everyone seems to be advocating beating them off the objective entirely, but it doesn't seem like you actually have that much space to work with. Sharpsburg is a fortress if either side gets an appreciable amount of defenders in it.

Yeah, and the AI seems NOT to retreat to sharpsburg (or a rear-objective in other battles) without losing the frontline one. This means that you can take your time completely surrounding the AI WITHOUT taking sunken road, because the AI wont fall back yet, and then move in and crush them when its too late.

Push them off the sunken road too early and they will fall back to sharpsburg before you have a chance to move around burnside's bridge

Remember: the AI doesnt have that many rearguard units holding far off positions. As far as I have seen, you often get to see 90 - 100% of the enemy's force at the main objective, meaning far off ones are undefended.

I use this tactic as union to beat malvern hill, because the main point is unholdable with that # of units, so what I do is fall back right away, let them chase me to the secondary objectives, then run soem cavalry up to take the main objective 10 minutes before the timer runs out. Their army is stuck in the middle not on the objective, while I have tons of men and time to just pick them off and snake out a technical victory.