For this post, let me pitch a curve ball – let it hang out there over the plate – and see if anyone crushes it. I’ll say this is but an interpretation that I ask you to roll around a bit to see how it fits.
If you’ve studied Major-General J.E.B. Stuart’s ride to Gettysburg, you are familiar with the story. Colonel Charles R. Lowell, commanding a battalion of the 2nd Massachusetts Cavalry, was supposed to be guarding Rowser’s Ford on the night of June 26-7, 1863. But a set of contradictory orders from Major-General Joseph Hooker, commanding the Army of the Potomac, and Major-General Samuel P. Heintzelman, commanding the Washington Defenses (22nd Corps if you wish). This missed assignment can be traced through a series of events to a proximate cause… well perhaps. So let me walk this one backwards to demonstrate.
First, the area of operations we are discussing – the western side of Montgomery County, Maryland:
This is a snip from Martenet and Bond’s map of Montgomery County, Maryland and more a political map than topographical (which is always my preference). But it will do. The map is oriented about 45° off to the right, with true north pointing roughly to the upper left corner. You see Poolesville in the middle with Edwards Ferry below; Rowsers Ford on the right and the Mouth of the Monocacy on the left.
As mentioned an earlier post, on June 25, Lowell received orders to cover the Potomac crossings, from the Mouth of the Monocacy to Great Falls. His command based out of Poolesville. Let me offer Lowell’s own words, from a letter to his future wife Josephine Shaw* written on July 1, 1863, the command confusion that occurred over those days in late June:
On Friday night [June 26] at half past ten, I got orders to report next day to General Slocum. As I had to get in my patrols from a space of over thirty miles and had besides to reduce the baggage of the Regiment from eight wagons to two, I didn’t start til 8:30 the next morning, made a comfortable march of twenty-five miles, reported as ordered, and went quietly into bivouac for the night, as I supposed. But at 11 came two dispatches from General Heintzelman, one ordering me to remain at Poolesville, or to return if I had left, the other notifying me that General Halleck sent the same order. I was considerably disturbed, and telegraphed at once to General Hooker and to General Heintzelman and notified General Slocum. In the morning, 4 o’clock, I got order from General Hooker to report to General French, and from French to report immediately; also orders from Heintzelman to take no orders that did not come through his, Heintzelman’s, Headquarters. This was embarrassing, but I decided with much reluctance to obey Heintzelman…. So I moved down the Potomac about fifty-seven miles, and, when I reached the mouth of the Monocacy, met some of my wagons with the news that the rebels in strong force had crossed the Potomac at the very ford I was especially to watch….
So this explains why no Federal pickets covered Rowser’s Ford on the night of June 27-28, leaving an open door into Maryland for Stuart.
But why was Lowell’s cavalry there in the first place? Days before they were covering the southern approaches to Alexandria (which, had they not moved, might have put them in contact with Stuart on June 26-7). But a shifting of cavalry detachments in Maryland left an opening that Lowell’s command had to fill. Lowell’s orders placed him in the operational sector controlled by Hooker, replacing a unit from Hooker’s Cavalry Corps. Over the previous week, Hooker had issued orders to other formations out of the Washington Defenses, particularly Major-General Julius Stahel’s division, without input from Heintzelman. So you might say Hooker had reason to assume Lowell was his to order about.
What was the unit shifted out of Maryland? A detachment of cavalry from the Reserve Brigade, Cavalry Corps, under Captain Samuel McKee had patrolled the area around the Mouth of the Monocacy from mid-June until June 23. At 11:35 p.m. on the evening of the 23rd, McKee received orders to “Report with your command to General Pleasonton at Aldie tomorrow. Cross at Chick’s Ford, if practicable.”
McKee’s men had to cross into Virginia and then of course cross back again in a few days. Why was McKee ordered to move? Well, on June 22, Brigadier-General Alfred Pleasonton, in a report to Hooker’s headquarters, suggested the move:
If it is deemed necessary that a force from this corps should remain on the Upper Potomac, I would request permission to relieve Captain McKee by a regularly organized force, but would respectfully suggest that some of the cavalry which is in Washington may be put upon that duty.
Why did Pleasonton want McKee back? Explaining his status after the fighting in Loudoun Valley, Pleasonton wrote, in the same report:
As an example of the reduction in numbers, I would state that, when the Reserve Brigade, consisting of the First, Second, Fifth, and Sixth U.S. and Sixth Pennsylvania Cavalry, went into action on the 21st instant, it only numbered 825 men, the remainder of the men of this brigade being either dismounted or at the mouth of the Monocacy with Captain McKee, who has or should have 1,100 men. Under these circumstances, I have the honor to request that Captain McKee’s command and all other effective men of this command may be ordered to join me at once, and that prompt measures may be taken to supply the number of horses that I need.
Most of the Reserve Brigade’s casualties came near the close of the fighting at Upperville. The brigade made an ill-fated charge on Vineyard Hill and suffered heavily for it.
If Pleasonton had not sent the Reserve Brigade into a difficult charge at Upperville, he wouldn’t have needed McKee at Aldie. Lowell would have remained in Virginia and might have encountered Stuart in Fairfax County instead of missing him in Montgomery County. And maybe someone would have been covering Rowser’s Ford on June 27-28. Or maybe not. Regardless, the reason Lowell was in Maryland to begin with was due to something that happened days earlier in Loudoun Valley. At a minimum, this demonstrates that operational moves don’t happen in a vacuum.
* Josephine Shaw was the sister of Robert Gould Shaw. This of course explains Lowell’s interest in events at Darien, subject of another post I’m working up.
(Citations from Life and Letters of Charles Russell Lowell: Captain Sixth United States Cavalry, Colonel Second Massachusetts Cavalry, Brigadier-general United States Volunteers, by Edward Waldo Emerson, pages 268-9; and OR, Series I, Volume 27, Part III, Serial 45, pages 258-9 and 273.)