03 January 2006 by Published in: Union Cavalry 19 comments

I have always bought into the school of thought that George B. McClellan made absolutely atrocious use of his cavalry. That’s the conventional wisdom, and in some ways, it’s a legitimate criticism. Instead of having his mounted units serve together as cohesive units during the 1862 Peninsula Campaign, he instead split up regiments and parceled them out, a company here and a company there, doing messenger and orderly duty, and not performing the traditional role of cavalry–scouting, screening, and reconnaissance. That is the conventional version of McClellan’s use of the cavalry. However, further digging has persuaded me that accepting that version dramatically underestimates the role that the cavalry played during his tenure in command of the Army of the Potomac.

As one example, McClellan used a cohesive command–the Cavalry Reserve–on the Peninsula, and, for the most part, it acquitted itself well. The Cavalry Reserve, consisting of the U. S. Army’s Regular cavalry regiments and supplemented by the Sixth Pennsylvania Cavalry, performed very well, particularly during the Fifth Corps’ combined arms operation that led to the Battle of Hanover Court House in May 1862. Then, the Army of the Potomac’s cavalry did some good work during the Maryland Campaign, and particularly at places like Quebec School House, where Federal horsemen gave Wade Hampton all he wanted. To be sure, his use of the cavalry was far from perfect–the failure to use any of his cavalry to picket the Harpers Ferry Road at Antietam is a glaring error that may have cost him an even greater success at Antietam. Instead, he used his cavalry to make a mounted charge across a bridge over Antietam Creek in an effort to capture or drive off some enemy artillery. While this was a decent use of cavalry pursuant to traditional Napoleonic tactics, it was not a good use of his horse under the circumstances.

At the same time, it’s clear to me that McClellan learned as he went along. I’ve never really looked at the period between Antietam and McClellan’s relief on November 7 before, but it’s very pertinent to my work on Ulric Dahlgren, so I’ve been examining it in some detail. When I looked at this period in detail, I discovered that the Union cavalry actually performed quite well in the Loudoun Valley during this period. Day after day, the Federal horse took on Jeb Stuart’s vaunted cavalry, and fought it to a standstill. It was hard, heavy fighting, and the Union troopers acquitted themselves quite well. Familar names such as George D. Bayard, David M. Gregg, and Alfred Pleasonton came to prominence during this period. Although Bayard had only a few weeks to live, the others had long careers in the Army of the Potomac’s Cavalry Corps and left their mark on the Union mounted arm. There’s not much out there on this period; Pat Brennan published an article that addressed this period in detail in a 1999 issue of Blue & Gray Magazine, and Pat–a cavalry guy–did an excellent job of documenting the relentless cavalry fighting that took place.

Most importantly, this period reflects that McClellan made good use of his mounted arm to perform the traditional role of cavalry–scouting, screening and reconnaissance–and that these men did an excellent job of screening his advance. It was, in fact, reminiscent of the fighting that took place on the same ground in the Loudoun Valley in June 1863, just a few months later. It is, therefore, clear to me that I have been unfair to George McClellan in the past, and that I need to be more open-minded about his use of cavalry. In fact, once he got past the Peninsula Campaign, he did rather well with his maturing mounted arm, the failure to picket the Harpers Ferry Road being the one really notable exception.

By contrast, Ambrose E. Burnside really was atrocious with his use of cavalry. The fact that there were exactly three casualties in the Union cavalry out of more than 13,000 suffered in the Battle of Fredericksburg is a pretty good reflection of just how badly he did. Bayard was one of the three, and his mortal wound was the result of bad luck–he was struck by a shell fragment while at Sixth Corps headquarters. When Bayard is removed from the equation, this means that there were exactly TWO Union cavalry casualties during the Battle of Fredericksburg. Clearly, Burnside was the worst of all of the Army of the Potomac’s commanders, not McClellan, when it comes to the use of cavalry.

It just goes to show you that the conventional wisdom is not always right, or if it is, it is an oversimplification of a complex issue that deserves a more detailed and more thorough examination. I’m glad that I have undertaken that task and come to different conclusions as a result.

Scridb filter


  1. Tue 03rd Jan 2006 at 10:43 pm

    Hi Eric,

    Let me just say, I don’t know squat about Cavalry ops, and I only know enough about Antietam to be dangerous. Could you amplify where you’re going with this statement:

    “… the failure to use any of his cavalry to picket the Harpers Ferry Road at Antietam is a glaring error that may have cost him an even greater success at Antietam”.

    What should he have done and what would it have got him?

    Looking at a map, I’d have thought that whole road out of McClellan’s reach from, say, 10-19 September.


  2. Tue 03rd Jan 2006 at 10:49 pm


    Thanks for writing.

    Actually, a rather large force of Union cavalry escaped from Harpers Ferry as Jackson bore down on them. They made their way back to the AoP via this road. McClellan could have dispatched his cavalry to block the road near Sharpsburg and could have slowed or delayed Hill’s division long enough for it not to have arrived at precisely the right moment to repulse Burnside’s assaults.


  3. Dave Kelly
    Wed 04th Jan 2006 at 10:24 am

    Get a little leary when when folks look at the senior leader and start commenting that the grass grew and the sun came up at the right point in the sky because they were in command. Same applies to Lincoln. A lot of process gets accomplished by subordinate functions that the boss scarcely influences beyond simply having it happen on his watch.

    Who were the cavalry maivens on McClellan’s staff pushing for a cavalry force? Who was teaching Mac to see cavalry as functional in the American Army? Cavalrys history was pretty shaky prior to the Civil War. The few regiments available tended to be Southern Gentleman’s club’s. Too many infantry types thought the cavalry died at Balaklava (Thin Red Line mythos, not the Lt Bde).

    At some point in time I was perusing the 7 Days OBs and was shocked to realize that at that point in the campaigning the AoP actually had slightly more cav than the ANV. As you have said, dogmatically the majority of these assets were penny packeted to the Infantry Corps.

    As to Burnside I’d have to look and see who ran the cavalry at the time. Burnsides failure is as much in how he was served as his own lack of knowledge of the branch.

  4. Wed 04th Jan 2006 at 11:27 am


    Good points, as always. To respond:

    1. Mac’s first chief of cavalry was Philip St. George Cooke, w ho was fired after the First Ride Around McClellan. George Stoneman, a hard-bitten old Regular horse soldie, took his place. On September 5, 1862, John Buford became chief of cavalry. Pleasonton had field command as the senior brigadier. Mac had some pretty good people around him.

    What amazes me, though, is that Mac was commissioned in the cavalry. He had also been an observer in the Crimea. The conventional wisdom was that it would take five years to train an effective volunteer cavalry force, and Mac accepted that.

    There are, of course, a multitude of things for which one can criticize John Pope. Use of cavalry, however, was not one of them. Pope demonstrated that brigades of volunteer cavalry could be effective, and to Mac’s credit, he accepted that at face value and began using them effectively after he assumed command of the defenses of Washington on September 5.

    2. Burnside’s chief of cavalry was also Buford. However, that was a purely administrative position that did not entail field command. The field commander was Pleasonton. In December 1862, Pleasonton recommended the formation of a formal cavalry corps, a recommendation accepted by Hooker in February 1863.

    All of this, by the way, is addressed at length in my book _The Union Cavalry Comes of Age: Hartwood Church to Brandy Station, 1863_, if it’s of interest to you.


  5. Dave Kelly
    Wed 04th Jan 2006 at 5:09 pm

    Forgot that Mighty Mac fenagled a commision in the 1st Cav in 1855. Don’t think he ever reported to the regiment, but headed off on the Delafield Commission to Europe shortly thereafter. His basic branch and service history was Engineer.

  6. Tom Clemens
    Wed 04th Jan 2006 at 5:10 pm

    I do not pretend to know about cavalry, or as we artillerymen call them, “the Buttermilk Rangers” but I too have some questions about picketing the Harpers Ferry Road. When exactly should that have happened? The only path to it was the bridge at Lime Kiln, and that was a long way from any infantry supports. Also, to turn an old argument to my favor, Lee had more cavalry than McClellan throughout the campaign up until the 17th wheen the HF cav. joined the AoP. If he sent a large portion off to picket that road he would be even less of a match for Stuart’s forces. HF rd. was too far out to send cavalry without sufficient infantry support, and he could not have blocked Hill’s march without being in Lee’s rear altogether. He certainly did not have enough cavalry for that.
    Secondly, his cavalry was, in part, inherited from Pope and the bloody fighting at Manassas took a heavy toll on the Union horsemen. Like much of the Union army, the cavalry was in rough shape and was being re-organized and re-supplied on the march.
    Also I think the move across Middle Bridge was less of a charge and more of a feint, but that is another can of worms.

  7. Wed 04th Jan 2006 at 7:24 pm

    Hi, Tom,

    Didn’t know you were a reader. Good to hear from you.

    Perhaps I was a bit too specific in what I was trying to say….it seems to me that Mac could have made a more efficient use of his cavalry in some fashion to attempt to block Hill’s route of march, as it was known that Hill was somewhere between Harpers Ferry and Sharpsburg. It seems to me that some sort of delaying action would have been a very effective and efficient operation.

    As for your point about the condition of those cavalry forces that had served with Pope, it’s well taken. There’s no doubt that they were in wretched condition, and thattheir horses were also in wretched condition.


  8. Stefan Papp, Jr.
    Thu 05th Jan 2006 at 3:21 am

    Stoneman was McClellan’s first chief of cavalry, Cooke never was. He commanded for some time the so called Reserve Brigade…


  9. Will Keene
    Thu 05th Jan 2006 at 3:56 am


    Hill didnt take the Harper’s Ferry Road. Hill’s route of march was on the south side of the Potomac until Boteler’s Ford. Mac had no troops in that area and could only have gotten them there by some great round about move via Williamsport or some such place.


  10. Thu 05th Jan 2006 at 9:30 am

    Well, I’ve never claimed to be an authority on Antietam. 🙂

    Thanks for setting me straight.


  11. Bob Fugate
    Thu 05th Jan 2006 at 7:18 pm

    Remember that in the days after Antietam and just prior to Mac’s removal from command, one of the controversies that exasperated Lincoln and Stanton was Mac’s insistence that the current poor state of his cavalry’s horses made more vigorous movement or pursuit of Lee impractical (when Lincoln famously wondered what they’d been doing that would have tired them out). Not taking sides in that dispute (although I’d give the benefit of the doubt to Mac, despite some historians’ snide view that it was just another excuse to delay action), it does further explain why Mac might not have used his cavalry more fully during the Antietam Campaign itself and up to the battle as you suggest.

  12. Thu 05th Jan 2006 at 10:52 pm


    In fairness most of the cavalry that was with Mac had come from Pope’s army, and it really was in absolutely wretched condition. Read the reports from Bayard and Buford during the Second Bull Run Campaign, and you will see what I mean. Pope’s insistence that the cavalry live off the land combined with overwork left it in terrible and inefficient shape.

    The truth is that Mac used it rather well just before Antietam–see Crampton’s Gap if you need an example–but seems to have dropped the ball a bit on the actual day of the battle.

    That’s my take, anyway.


  13. Will
    Fri 06th Jan 2006 at 3:17 am

    Eric wrote: “In fairness most of the cavalry that was with Mac had come from Pope’s army.” Tom made a similar remark.

    I question this. Compare the cavalry units in Pope’s army with those under Pleasanton in Maryland. I think you will find barely any overlap. Compare Pelasanton’s units to those that served on the peninsula and I think you will find they match. When Mac marched across Maryland, the bulk of what had been Pope’s cavalry remained with the forces defending Washington and operated in nothern Virginia.

  14. Bob
    Sat 07th Jan 2006 at 12:04 am

    Eric, I’m near the end of The Union Cavalry Comes of Age and have enjoyed it very much. I don’t think the story was told well at all previously. Prompted by your post, I hope that you’ll undertake a work on the Union cavalry’s more formative period priot to 1863. There’s a lot there that similarly hasn’t been studied in depth. For example, we read a lot of brief mentions of George Bayard and how well he was regarded, but the historians have generally ignored him up to now. And a more in-depth study of Mac’s use of cavalry would be a contribution, including the activities on the Peninsula and why it evolved differently than that of the South. It wasn’t for want of qualified leaders. I think you’d find a lot of interest on the subject.

  15. Sat 07th Jan 2006 at 12:09 am


    Thanks for your kind words–I’m pleased to hear that you’re enjoying the book and that you find something worthwhile in it.

    Funny you should mention this–my buddy J. D. Petruzzi and I had a discussion about covering the fighting in the Loudoun Valley in the fall of 1862 just this afternoon. As for the Federal cavalry on the Peninsula, my friend Bob O’Neill has been working on just that for some time.


  16. Dave
    Mon 09th Jan 2006 at 11:52 pm

    It takes (roughly) about ten pounds of grain and ten pounds of hay to keep an active horse fit. These are rough figures, but that’s in the ballpark. If Pope expected his Cavalry to be able to “live off the land” and conduct extended operations at the same time then he was a d*mned fool.

    You can get away with foraging for your forage for a short time, but horses can and will lose weight and condition rapidly. This is a guess, but I’d think no more than two to three weeks of operations under these conditions before the animals wouldn’t be fit anything.

    I have no idea how many horses Pope’s Cavalry had, but figure at least ten thousand? Foraging for that many horses would be a full time job in and of itself.

  17. Dave
    Mon 09th Jan 2006 at 11:54 pm

    Second paragraph, last sentence; “fit for anything”

    sorry ’bout that.

  18. Tue 10th Jan 2006 at 10:09 am


    It was more like 5,000 or 6,000, but your point is nevertheless very well-taken. Thanks for pointing that out.


  19. Will Keene
    Wed 11th Jan 2006 at 12:59 pm

    “The fact that there were exactly three casualties in the Union cavalry out of more than 13,000 suffered in the Battle of Fredericksburg is a pretty good reflection of just how badly he did.”

    I dont know anything about Burnside’s use of cavalry, but I also dont folow your logic here. Are casualties a measure of good generalship?

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