Maryland 1862 Campaign - the umpire's view

This is the campaign umpire's debriefing - by Peter Williams:

 

Thanks to Mark and Jim and Nick for putting in all the real work. I had the fun of watching both armies blundering around in the dark and I could make rulings about issues that cropped up, each of which I knew would upset either the ANV or the AOP. I’m happy to be corrected in my opinions below about why the generals did certain things. It was often a mystery to me.

Phase 1 from Day 1 to day 4

The opening three day turn, and the day after, went similar to the real thing. The AOP, already deployed within a couple of hexes of Washington, rested and saved force marches, then headed a bit north-west to cover both Baltimore and Washington while their cav went out to find the ANV.

The ANV began mostly south of Frederick . It split, part going to take Harpers and part heading north via Mechanicsville- a departure from what General Lee did. In my view the first major error occurred here, when the ANV cav div marched via Sharpsburg to attack Harpers. On the second attempt Harpers fell, but the consequence was the ANV cav was unable to do its main job-screen the army and go looking for the AOP so, for the rest of the campaign the ANV was in the dark about the whereabouts of the AOP.

Phase 2 from day 5 to day 7

By day 5 the AOP knew where the ANV was, but not visa versa. That day the ANV main body (apart from 4 div and the cav which together captured Harpers) had a div at Cashtown, 2 more at Gettysburg and one at Hannover. Apart from sending the Cashtown div to Gettysburg, there they stayed resting until the beginning of their march on Baltimore on day 8.  

In phase 2 the AOP was moving west through the mountains with a view to taking Sharpsburg and Williamsport, thus denying the ANV a Victory Point and, I think, assuming the ANV was about to come that way via Waynesboro. This AOP advance caught up with the ANV’s 4^th div, which had participated in both Harpers battles. It was lucky to survive when the AOPs 2^nd Corps caught up with it north of Sharpsburg on day 7. As a result of the battle there ANV’s 4^th div retreated, shattered, across the Potomac at Williamsport and took no further part in the campaign. It had with it the extra artillery ammo captured at Harpers; the ANV was short of arty ammo and, had the battle at Baltimore gone all day that second decisive day, day 12, then I expect the rebs would have run out of artillery rounds.  

Phase 3 from day 8 to day 12

On day 8 the ANV main body commenced its march from Gettysburg via Hannover to Baltimore. I’m not sure the ANV had intended this from the start of the campaign. The AOP was in a tricky situation at this point. Having committed corps west of the mountains to deny the ANV the victory point by taking Sharpsburg and Williamsport, the AOP also felt it had to retain some troops east of the mountains just in case of an advance on Washington and Baltimore.  With hindsight a better move might have been to advance against the ANV once, by day 6, they were sure it was in the Gettysburg region.

As it happened, by the end of day 8 the ANV had advanced towards Baltimore to 1410, two hexes east of Hannover, while the Union still had three corps in the Sharpsburg - Williamsport region west of the mountains and another three on the east side at Jefferson, Frederick and Ridgeville. Unfortunately the two easternmost AOP corps, closest to Baltimore, were also the two worst.

The AOP had cav watching the head of the ANV column from Hannover all the way to Baltimore, so on day 9 the AOP knew enough to respond to the ANV’s march. The reason the ANV was unable to do anything about Union cav watching it was its own cav were still coming in from Harpers by a roundabout route, only rejoining the ANV main force on the first day of the battle of Baltimore. Around this time the AOP requested extra troops from the Washington garrison and, as this was what really happened in 1862 (but they arrived just too late for the battle of Antietam) Lincoln released 4 C class stands which I called 7^th Union Corps. They fought at Baltimore.

On the approach to Baltimore both generals ran up against, complained about, and had to work out how to make most effective use of the road movement bonus rule- there are only so many corps (Union) or divisions (ANV) that can get the road movement bonus on any day in any road hex. The ANV solution was to rest alternate divs off road while others marched through, which resulted in a slower advance than would have occurred if two roads were used. The AOP solution was to use two roads out of Frederick, one to Elkridge and the other to Westminster.

The battle which resulted at Baltimore on days 11 and 12 went the way it did, perhaps, because the AOP spent one day too long waiting to be sure that the ANV advance was not a feint. The AOP was also preparing a trap and at the end of day 12, the final day, they had a large force in the ANV rear: their cav was at Cockeytown and they had an infantry corps each at Manchester and Westminster. Had Baltimore held, or had the AOP response been executed one day earlier, then the ANV, which was outnumbered by the AOP almost 2-1, would probably have been cornered and eliminated day 14 or 15 somewhere north-west of Baltimore.

Summary

The AOP handled the campaign better for the first two of the three phases, but not in the third phase, the march on Baltimore.

I’m surprised the ANV won as they misused their cav, so had little idea of where the AOP was, other than having some indication that a lot of it was, by day 7, west of the mountains. I think the ANV only came up with a real plan on day 8, but they did manage to get to the decisive point firstest with the mostest, and that is what counted in the end.