Download Click here to view animation.

Alesia
September, 52 BC
Strategic Context
Julius Caesar considers Gaul secure until it revolts under the leadership of Vercingetorix, an
Arverni chieftain. Vercingetorix does not rely on an impulsive, barbarian offensive strategy as
Caesar expects. Instead, the Gauls do not allow a decisive battle to take place for fear it will
be a decisive defeat, and fight a partisan war by retreating and destroying everything behind
them. Caesar grows impatient, especially after the failed assault against the fortress of
Gergovia and the inconclusive skirmish at the Vingeanne. Vercingetorix retires to Alesia and
Caesar follows; it appears Vercingetorix, pressured by his allies, is finally giving battle.
To view animation on PC: hit F5
To view animation on Mac: hit ⌘ + enter
Stakes
+ A Roman victory would crush the Gallic
revolt and remove Vercingetorix as a
nuisance for good.
+ A Gallic victory would heighten the
insurrection and threaten Roman control
over the entire region.
By Jonathan Webb, 2009
Alesia, 52 BC
Strength
Romans
Gauls
Julius Caesar
Vercingetorix
40,000 infantry
15,000 cavalry
150,000 infantry
23,000 cavalry
Well
Well
By Jonathan Webb, 2009
Roman Empire c. 52 BC
The fort of Alesia sits atop the steep western hill of Mount Penneville, surrounded by rivers, valleys, and then hills a little further out,
making approach difficult from three sides. The steepest and most elevated terrain is to the north in the form of Mount Rea and Mount
de Bussy. The flattest terrain is to the southwest where the Heights of Mussy-le-Fosse give way to the Plain of Laumes.
Romans
(Caesar)
Mount Rea
Mount de Bussy
Rabutin River
Oze River
Alesia
Brenne River
Ozerain River
Plain of Laumes
Mount Penneville
Heights of Mussyle-Fosse
N
Gauls
(Vercingetorix)
Mount de Flavigny
0
1
2
3 km
Vercingetorix’s
force
within
Alesia
runs
out
of supplies
and
hope
just
as
ahis
massive
Gallic
relief
army
arrives,
ledditch
byare
four
other
chieftains.
Some
Gallic
rush
Themidnight,
At
Romans
the
begin
construction
relief
army
on
launches
lines
ofan
contravallation,
attack
on builds
the
western
extensive
side
barriers
of
the walls
Roman
to two
prevent
fortifications.
Gauls
Caesar
ininsufficient
Alesia
is able
from
to transfer
escaping
reinforcements
and
protect
the
to
The
same
night
theGallic
Romans
complete
construction,
Vercingetorix
sends
cavalry
away
for
reasons:
there
supplies
to feed
theinfantry
riders along
Caesar
surrounds
Alesia
with
his
entire
force,
and
some
earthen
and
a the
wide
on
the
western
plain.
He
decides
to
out
to
begin
filling
the
wide
ditch
in
anticipation
of
an
immediate
assault
by
the
relief
army.
However,
the
relief
army
is
unprepared
to
make
such
a
hasty
assault
Romans
the
threatened
from
any
sectors
attack
by
and
them.
repel
These
the
fortifications
attack
decisively,
face
inward
but
only
and
after
consist
heavy
of
a
fighting
double
ditch
from
backed
behind
by
his
a
12-foot
extensive
high
lines
rampart,
of
circumvallation.
missile
towers,
with
their
animals.
and
reinforcements
must
be
summoned
immediately.
The
exhausted
Romans
are
unable
to
intercept
the
Gallic
cavalry
but
their
punishing
blockade
rather than
assault
theout
city
because
ofchallenge
its naturally
fortified
position
andcavalry
the large
Gallic The
force
within it.forces
At first,
Vercingetorix
after
a long
so
Caesar
sendshis
his
cavalry
thefortifications,
Gallic
relieflearns
army’s
small
contingent.
exchange
blows
all
defences
stilljourney
inflict
casualties.
Caesar
orders
atosecond
line army
of
lines
of
circumvallation,
to bethe
built
to two
defend
against
an
attack
from
a Gallic
and macabre
Vercingetorix
traps,
triesheavy
to
many
coordinate
invented
byattack
Caesar
with
and
the
his
relief
men,
littered
buteverywhere
only
possible.
of
the
attack
Vercingetorix
when
sends
Romans
his cavalry
cavalry
do.
His
toinfantry
halt
construction
are
therefore
of
encamps
his
force
on
Alesia’s
slopes
because
he
expects
Caesar
to
attack
from
the
east
before
reinforcements
can
be
summoned.
afternoon
until
the
Roman
cavalry
finally
defeat
the
Gauls
and
chase
them
from
the
field,
discouraging
the
besieged
Gauls
as
Caesar
intended.
relief army. This second line is just as savage and fortified as the first except this one faces outward.
such a ruthless
delayed
by the first
line wide
of defence
ditch and
but reach
Caesar’s
battle
cavalry
too late
drive
tothem
aid the
back
relief
to Alesia;
army’s construction
efforts. Gaulscontinues
on both sides
untilof
completion.
Roman lines retire to their camps.
Gauls
Romans
(Vercingetorix)
(Julius
Caesar)
150,000
infantry
40,000 infantry
23,000 cavalry
15,000
Romans
(Caesar)
Symbol guide
Mount Rea
Mount de Bussy
Rabutin River
Oze River
Vercingetorix
Romans
Gauls
Alesia
Infantry
Infantry
Cavalry
Cavalry
Brenne River
Ozerain River
Plain of Laumes
Mount Penneville
Heights of Mussyle-Fosse
Gauls
(Vercingetorix)
N
Commius/
Vercassivellaunus/
Viridomarus/
Epoderix
Landmarks
Mount de Flavigny
0
1
2
3 km
The
Gauls isscout
theGallic
impressive
Roman
lines
for weaknesses
before
considering
another
assault.
The Gallic
leaders
theCaesar’s
most
vulnerable
sectorreinforcements
to
be his
the presence
northwest
At
midnight,
the
relief
army
launches
anthe
attack
on the
western
side
the
fortifications.
is able
to
transfer
to
Fighting
desperate
in all
sectors,
in
northwest
the
Romans
areRoman
under
attack
fromdetermine
twoCaesar
sides.
fortifications
and
Vercingetorix
hisespecially
subordinates
to
aofwhere
council
andof proposes
a surrender.
have
suffered
grave
corner where a steepsummons
hill prevents proper
fortification.
Under cover
night,
Vercassivellaunus
leads a strong
infantry force The
behindGauls
the nearest
hill; he
strikes against
this
the threatened
sectors and
attack decisively,
butsector
only inspires
after heavy
fighting
from the
behind
linesHeofis circumvallation.
prove
their worth everywhere.
Hisrepel
timelythe
appearance
in the southern
his infantry
to defeat
Gauls his
and extensive
end this threat.
then able to shift
vulnerable
place in
daylight
while
the breached
rest of the relief
armyRoman
parades infortifications
front of their camp. while
This massive
attackhas
is somehow
coordinated None
with Vercingetorix
who simultaneously
casualties,
have
not
yet
the
noRoman
supplies.
of infantry
histhesubordinates
reinforcements
over
to
the
northwest
sector
hold
while
he sends
his but
cavalry
outside
fortifications.
The
cavalry
sweep
across
flank
rear of
Vercingetorix
tohelp
coordinate
hisRoman
attack
with
the relief
army
only
learnsthe
ofAlesia
the attack
when
Romans
do. His
are and
therefore
sends his infantrytries
against
three
sides of the
lines
of contravallation,
one of
which
dismisses
the
attack
almost at
once.the
Caesar
sends reinforcements
to wherever
is needed
the
heavily
committed
Gallic
infantry,
scattering
the
entire
force.
Vercingetorix
sees
the
attack
has
failed
and
once
again
retires
to
Alesia.
object.
Vercingetorix
personally
surrenders
to
Caesar
while
nearly
every
Gallic
tribe
involved
also
capitulate.
delayed
by
the
first
wide
ditch
and
reach
battle
too
late
to
aid
the
relief
army’s
efforts.
Gauls
on
both
sides
of
Roman
lines
retire
to
their
camps.
at that very moment.
Gauls
Romans
(Vercingetorix)
(Julius
Caesar)
150,000infantry
infantry
40,000
23,000 cavalry
15,000
Romans
(Caesar)
Vercassivellaunus
Symbol guide
Mount Rea
Mount de Bussy
Rabutin River
Oze River
Vercingetorix
Romans
Infantry
Brenne River
Cavalry
Gauls
Alesia
Infantry
Cavalry
Ozerain River
Plain of Laumes
Mount Penneville
Heights of Mussyle-Fosse
Gauls
(Vercingetorix)
N
Commius/
Commius/
Vercassivellaunus/
Viridomarus/
Viridomarus/
Epoderix
Epoderix
Landmarks
Mount de Flavigny
0
1
2
3 km
Alesia, 52 BC
Casualties & Aftermath
Romans:
Gauls:
12,000
>40,000
or
or
22%
23%
The majority of the Gallic tribes immediately bowed down to Roman authority
while Vercingetorix was taken to Rome and executed. The few resisting tribes
still active were individually hunted down and defeated by Caesar the following
year, ending the insurrection. Gaul remained pacified and part of Rome for a
thousand years after its final conquest.
By Jonathan Webb, 2009
The Art of Battle:
Animated Battle Maps
http://www.theartofbattle.com
By Jonathan Webb, 2009