1204: Philip Augustus seized Château-Gaillard. This assault marked
the end of the systems of passive defence. The great changes of the
13th century had their origins in the late XIth century when the Christian
lords found themselves confronted in the East with a defensive system
dating back to the earliest times of Antiquity - Byzantium alone had
kept using these techniques. The fortified castles of Palestine (including
the famous Krak of the Knights - Crac des Chevaliers - built in Syria
in 1180) were the first to take advantage of these techniques.
Although the English King Richard the Lionheart was the first, when
building Château-Gaillard, to bring these new techniques into Europe,
they were systematically used by Philip Augustus. After creating the
first corps of military engineers (who played an essential part in the
Albigensian Crusade) he used these new techniques in the building of
many fortified castles as well as in the rebuilding of the fortresses
he seized from the English.
From then on the building of fortresses was no longer the effect of
experience and personal power - the characteristic of feudalism - it
became part of a logic of State. Apart from a few exceptions, most of
the French royal military buildings in the XIIIth century were commissioned
by kings and were carried out by great architects (such as Eudes de
Montreuil for Saint Louis or Egidio Collona for Philip the Fair).
The XIIIth century brought a complete change. With the growing number
and the improvement of war-machines the defensive system was forced
to become more effective: the arrow-slits became more numerous and their
shape more varied; wooden galleries were gradually replaced by machicolations
- which were used for the first time in Niort in 1170; the first drawbridges
also appeared; square towers were replaced by round towers which, being
stronger, allowed better flanking. Real active defence, however, did
not lie so much in the putting into practice of these new techniques
as in the new arrangement of the different elements composing the defensive
system: standardized as it was under the influence of the military engineers,
the fortified castle became more practical.
The quadrangular plan was adapted, the enceinte was topped by machicolations
and was systematically built with a sloping base (so as to prevent mining
and to allow the rebounding of missiles thrown from the top of the battlements).
Straight curtain walls were interspersed with salient towers, one being
placed on either side of the main gate. These round towers were vaulted
on all levels to limit the risks of fire. Thus strengthened, and sometimes
equipped with its own water tanks and storage rooms, each of them was
an independent small keep.
The whole fortress might also be surrounded by an additional outer jacket
wall lower than the inner one so as not to hinder the firing from the
main building. The outer moat was enlarged and could be ten metres deep
and fifteen metres wide. Where possible, it was full of water - in order
to protect the approaches. Thus defended, the enceinte was provided
with numerous arrow-slits in staggered rows; it was protected by towers
at regular intervals and became a formidable obstacle with considerably
fewer blind angles than in the preceding centuries.
Inside the castle, more space was cleared to allow movement; the castle
was arranged as follows: the lord's living quarters, the outbuildings
and the chapel - all stood against the enceinte. The stress was no longer
laid on placing an endless series of obstacles (which finally turned
to the disadvantage of the besieged) but on establishing a single line
of defence against which the main building and the outbuildings stood.
The keep was generally circular in shape and consequently ill-adapted
to lodging. Its part was therefore essentially military. It was at first
situated outside the enceinte and linked to the rest of the defensive
system by a footbridge or a drawbridge - thus remaining the last retreat
- but was also henceforth ready to receive reinforcements or to launch
a counter attack towards the castle. When maintained in the centre of
the castle (as in the Louvre for example), it was only a symbol of authority.
After the reign of Philip Augustus, the keep was again included in the
line of fortified walls, its enormous size alone making it stand out
among the other towers. These changes sometimes led to the disappearing
of the keep as in Carcassonne.