Battle Ranks in ROTD
ROTD uses the idea of battle ranks to convey the tactical plans of
the attacking commanders and, primarily, the sequence in which they
commit units to battle. Because one tactical phase represents three
or four hours of fighting, ranks do not represent battle formation;
during one tactical phase, units have time to shift position, pass
lines, and so forth. Instead, "rank" is intended to achieve three
things, one primary one it was designed to do, and two more that it
picked up along the way.
The primary one is that it captures the sequence in which units are
committed to battle. Units in the first rank are the ones that
engage right away; they fight at the time when the two sides are
initially closing with one another. Units in the second rank are
committed to battle once the first ranks are engaged. They generally
are more effective in combat than units in the first rank, because
the battle situation is already developed by the time they go in and
they can be sent to critical locations, also because they don't take
damage on the way into combat; they come up behind the units in the
first rank. Units in the third rank are only committed once the
units in the first two ranks are already in. That means they won't
fight for quite a while, by which time the battle may be already won
or lost; it may also be hard to find places where they can be used
effectively. So they fight at half strength.
The second thing that ranks do is capture the effect of tactical
planning. If a side has put too much manpower in the first or second
rank, then that manpower fights at half strength, which obviously
reduces its side's effectiveness. Sides which get the right number
of men in each of the ranks get a tactical edge over sides that are
not careful about that. It also means that attacks are more
effective in tactical phase 1, at which time attacks can be
carefully planned out, than they are in later tactical phases where
the situation is more fluid and it's harder to arrange units into
just-filled ranks.
The third thing that ranks do is capture the role of infantry in
protecting artillery; ROTD treats first-rank infantry as supporting
second-rank artillery, so that artillery fights better when it has
infantry protecting it than when it doesn't. This doesn't quite
match the purpose of representing the order of engagement, because
in such a case, the artillery would be the first unit to engage as
the enemy approached, then the infantry would move forward once the
two sides got into rifle range. But by the time the infantry has
engaged the artillery is behind the infantry; so at that point the
two concepts match.
Example: consider Longstreet's attack on day 2 at Gettysburg.
Longstreet is attacking with 8 IN and 4 LA. Sickles is defending
with 6 IN and 1 LA of III Corps, and will get 6 IN and 1 LA from II
and V Corps as reinforcements during the battle.
Consider a tac map with the Peach Orchard at 7-7, the Round Tops at
8-9, and the Devil's Den in 7-8. Sickles is initially deployed with
2 IN at 7-6, 2 IN at 7-7 and his LA at 7-7, and 2 IN at 7-8. He
doesn't have enough troops to extend one more tac square to the
Round Tops at 8-9. 4 IN and 1 LA from V Corps are at 9-6, and 3 IN
from II Corps are at 8-6. The Confederates are deployed with 2 IN
and 1 LA (McLaws) at 6-7, 2 IN and 1 LA (McLaws) at 6-8, and 4 IN
and 2 LA (Hood) at 6-9. Observe that the Confederates can't see the
Union V Corps stack at 9-6, but they can see that the Round Tops at
8-9 are unoccupied.
The Confederates order one IN (Law's brigade) to from 6-9 via 8-9 to
7-8, trying to lengthen the line of the attack against the Union
stack at 7-8. However, two IN and the LA from the Union V Corps
stack at 9-6 move to 8-9 (Round Tops) and one of their IN (Vincent)
moves first. So one of Hood's IN hits that stack, and ends up
fighting at LRT at 8-9 against two Union IN and 1 LA. Hood's other 3
IN and his 2 LA attack 7-8, some going by 7-9 and some directly from
6-9. McLaws puts one of his IN at 6-8 into 7-8 as well, and the rest
of his units into the Peach Orchard at 7-7. The other two IN from
the V Corps stack at 9-6 move to 7-7 also. The Union II Corps
brigades move to 7-8. RH Anderson's division's attack pins the other
two brigades of III Corps at 7-6; they don't fight against
Longstreet, and I won't consider RH Anderson's part of the battle in
this example.
Battle ranks are as follows:
In 8-8 (Little Round Top), the battle front is 1000 yards. Law's
brigade is in the front rank for the Confederacy. Vincent's and
Weed's brigades are front rank for the Union, and the V Corps
artillery is second rank.
In 7-8 (Wheatfield/Devil's Den) the battle front is 2000 yards due
to attacks from S and W. Confederate front rank units are Benning's,
GT Anderson's, and Robertson's brigades, second rank are Semmes'
brigade and Henry's and Alexander's artillery. On the Union side,
Ward and DeTroibriand are first rank, and the supporting brigades of
Kelly, Brooke, and Cross are all in second rank, which they overfill
somewhat.
In 7-7 (Peach Orchard) the battle front is 1000 yards. Confederate
front rank units are Kershaw and Barksdale, second rank is Wofford
and Cabell and Eshelman's artillery. Both ranks are a little
overfilled. Union front rank units are Graham and the III Corps
artillery (bad placement by Sickles), second rank units are Sweitzer
and Tilton, Burling is in rear rank.
That doesn't quite match the real battle perfectly, but it's pretty
close; close enough for the limited level of tactical detail that
ROTD aims to represent.
Maintained by Steve Schmidt; last updated 12-31-15