A
star fort or
trace italienne is a
fortificationFortifications are military constructions and buildings designed for defense in warfare and military bases. Humans have constructed defensive works for many thousands of years, in a variety of increasingly complex designs...
in the style that evolved during the age of black powder, when
cannonA cannon is any tubular piece of artillery that uses gunpowder or other usually explosive-based propellants to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
s came to dominate the
battleGenerally, a battle is a conceptual component in the hierarchy of combat in warfare between two or more armed forces, wherein each group will seek to defeat the others within the scope of a military campaign, and are well defined in duration, area and force commitment.Wars and military campaigns...
field, and was first seen in the mid-15th century in
ItalyItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
. Passive ring-shaped (
enceinte)
fortifications of the medieval eraMedieval fortification is the military aspect of Medieval technology that covers the development of fortification construction and use in Europe roughly from the fall of the Western Roman Empire to the Renaissance...
proved vulnerable to damage or destruction by cannon-fire, when it could be directed from outside against a perpendicular masonry wall. In contrast, the star fortress was a very flat structure composed of many triangular
bastionA bastion is a structure projecting outward from the main enclosure of a fortification, situated in both corners of a straight wall , facilitating active defense against assaulting troops...
s, specifically designed to cover each other, and a ditch. Further structures such as
ravelinA ravelin is a triangular fortification or detached outwork in front of the bastions of a fortress. Originally called a demi-lune, after lunette, the ravelin is placed outside a castle opposite a fortification curtain. The edges of the ravelin are placed so that the guns there can sweep fire upon...
s, hornworks or
crownworksA Crownwork is an element of the Italian Bastion system of fortification and is effectively an expanded Hornwork. It consists of a full bastion with the walls on either side ending in half bastions from which longer flank walls run back towards the main fortress.The crownwork was used to extend...
, and detached forts could be added to create a complex symmetrical structure.
Star fortifications were further developed in the late fifteenth and early sixteenth century in response, primarily, to the French invasion of the Italian peninsula. The French army was equipped with new
cannonA cannon is any tubular piece of artillery that uses gunpowder or other usually explosive-based propellants to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
s and
bombardsA bombard is a large-caliber, front-loading medieval cannon or mortar, used chiefly in sieges for throwing heavy stone balls. The name bombarde was first noted and sketched in a French historical text around 1380. The modern term bombardment derives from this.Bombards were usually used during...
that were able to easily destroy traditional fortifications built in the
Middle AgesThe Middle Ages of European history is a period of European history covering roughly a millennium in the 5th century through 16th centuries. More specific starting and ending points are sometimes adopted by scholars to suit their respective specializations or current focus...
. In order to counteract the power of the new weapons, defensive walls were made lower and thicker. They were built of many materials, usually earth and
brickA brick is a block of ceramic material used in masonry construction, usually laid using mortar.-History:The oldest shaped bricks found date back to 7,500 B.C. They have been found in Çayönü, in the upper Tigris region, and in south east Anatolia close to Diyarbakir. Other more recent findings,...
, as brick does not shatter on impact from a cannonball like
stoneIn geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...
does. Another important design modification was the
bastionA bastion is a structure projecting outward from the main enclosure of a fortification, situated in both corners of a straight wall , facilitating active defense against assaulting troops...
s that characterized the new fortresses. In order to improve the defense of the fortress, covering fire had to be provided, often from multiple angles. The result was the development of "star"-shaped fortresses.
They were employed by
MichelangeloMichelangelo di Lodovico Buonarroti Simoni , commonly known as Michelangelo, was an Italian Renaissance painter, sculptor, architect, poet, and engineer...
in the defensive earthworks of
FlorenceFlorence is the capital city of the Italian region of Tuscany and of the province of Florence...
, refined in the sixteenth century by
Baldassare PeruzziBaldassare Tommaso Peruzzi was an Italian architect and painter, born in a small town near Siena and died in Rome. He worked for many years, beginning in 1520, under Bramante, Raphael, and later Sangallo during the erection of the new St. Peter's...
and
Scamozzithumb|250px|Portrait of Vincenzo Scamozzi by [[Paolo Veronese]]Vincenzo Scamozzi was an Venetian architect and a writer on architecture, active mainly in Vicenza and Venice area in the second half of the 16th century...
.
The design spread out of Italy in the 1530s and 1540s. It was employed heavily throughout Europe for the following three centuries. Italian engineers were heavily in demand throughout Europe to help build the new fortifications.
The late-seventeenth-century architect
Menno van CoehoornMenno, baron van Coehoorn , was a Dutch soldier and military engineer of Swedish extraction. He made a number of influential weaponry innovations in siege warfare and fortification techniques...
and
VaubanSébastien Le Prestre, Seigneur de Vauban and later Marquis de Vauban , commonly referred to as Vauban, was a Marshal of France and the foremost military engineer of his age, famed for his skill in both designing fortifications and in breaking through them...
,
Louis XIVLouis XIV , popularly known as the Sun King , was King of France and of Navarre His reign, from 1643 to his death in 1715, lasted seventy-two years, three months, and eighteen days, and is the longest documented reign of any European monarch.Louis began personally governing France after the death...
's military engineer, are considered to have taken the form to its logical extreme. "Fortresses... acquired
ravelinA ravelin is a triangular fortification or detached outwork in front of the bastions of a fortress. Originally called a demi-lune, after lunette, the ravelin is placed outside a castle opposite a fortification curtain. The edges of the ravelin are placed so that the guns there can sweep fire upon...
s and
redoubtA redoubt is a fort or fort system usually consisting of an enclosed defensive emplacement outside a larger fort, usually relying on earthworks, though others are constructed of stone or brick. It is meant to protect soldiers outside the main line of defense and can be a permanent structure or a...
s, bonnettes and
lunettesIn fortification a lunette was originally an outwork of half-moon shape; later it became a redan with short flanks, in trace somewhat resembling a bastion standing by itself without curtains on either side. The gorge was generally open....
, tenailles and tenaillons, counterguards and crownworks and hornworks and curvettes and fausse brayes and scarps and cordons and
banquetteIn fortification, a banquette is a little foot path or elevated step along the inside of a rampart or parapet, by which the musketeers get up to view the counterscarp, or to fire on the enemies in the moat. These are generally a foot and a half high, and almost three feet wide.A banquette may also...
s and
counterscarpA scarp and a counterscarp are the inner and outer sides of a ditch used in fortifications. In permanent fortifications the scarp and counterscarp may be encased in stone...
s..."
The star-shaped fortification had a formative influence on the patterning of the Renaissance
ideal cityUrban, city, and town planning is the integration of the disciplines of land use planning and transport planning to explore a very wide range of aspects of the built and social environments of urbanized municipalities and communities...
: "The Renaissance was hypnotized by one city type which for a century and a half—from Filarete to Scamozzi—was impressed upon all utopian schemes: this is the star-shaped city."
In the nineteenth century, the development of the explosive shell changed the nature of defensive fortifications.
Origins
The predecessors of star fortifications were
medieval fortressesMedieval fortification is the military aspect of Medieval technology that covers the development of fortification construction and use in Europe roughly from the fall of the Western Roman Empire to the Renaissance...
, usually placed on high
hillA hill is a landform that extends above the surrounding terrain, in a limited area. Hills often have a distinct summit, although in areas with scarp/dip topography a hill may refer to a particular section of scarp slope without a well-defined summit A hill is a landform that extends above the...
s. From there
arrowAn arrow is a pointed projectile that is shot with a bow. It predates recorded history and is common to most cultures.- Structure :A normal arrow consists of a shaft with an arrowhead attached to the front end, with fletchings and a nock at the other....
s were shot at the enemies, and the higher the fortress was, the farther the arrows flew. The enemies' hope was to either ram the gate or climb over the wall with
ladderA ladder is a vertical or inclined set of rungs or steps. There are two types: rigid ladders that can be leaned against a vertical surface such as a wall, and rope ladders that are hung from the top. The vertical members of a rigid ladder are called stringers or stiles...
s and overrun the defenders. For the invading force these fortifications proved quite difficult to overcome. Therefore, fortresses occupied a key position in warfare.
When the newly effective maneuverable siege cannon came into military strategy in the fifteenth century, the response from military engineers was to arrange for the walls to be embedded into ditches fronted by earth slopes so that they could not be attacked by destructive direct fire, and to have the walls topped by earth banks that absorbed and largely dissipated the energy of
plunging firePlunging fire is gunfire directed upon an enemy from an elevated position or gunfire aimed so as to fall on an enemy from above. In naval warfare plunging fire was often used to penetrate an enemy ship's thinner deck armor rather than firing directly at an enemy ship's side...
. Where conditions allowed, as in
Fort ManoelFort Manoel is a fortification on the island of Malta. It stands on Manoel Island in Marsamxett Harbour to the north west of Valletta and commands the entrance to Marsamxett Harbour and the anchorage of Sliema Creek.-General:...
in
MaltaMalta , officially the Republic of Malta , is a densely populated developed European country in the European Union. The Southern European island nation is an archipelago that includes the inhabited islands of Malta, Gozo and Comino, along with a number of smaller, uninhabited islands...
, the "ditches" were cut into the native rock, and the "wall" at the inside of the ditch was simply unquarried native rock. As the walls became lower, they also became more vulnerable to assault.
Worse yet, the rounded shape that had previously been dominant for the design of turrets created "dead space" or "dead" zones (see figure) which was relatively sheltered from defending fire, because direct fire from other parts of the walls could not be shot around the curved wall. To prevent this, what had previously been round or square turrets were extended into diamond-shaped points to give storming infantry no shelter. The ditches and walls channeled attacking troops into carefully constructed killing grounds where defensive cannons could wreak havoc on troops attempting to storm the walls, with emplacements set so that the attacking troops had no place to shelter from the defensive fire.
A further and more subtle change was to move from a passive model of defense to an active one. The lower walls were more vulnerable to being stormed, and the protection that the earth banking provided against direct fire failed if the attackers could occupy the slope on the outside of the ditch, and mount an attacking cannon there. Therefore, the shape was designed to make maximum use of enfilade (or "flanking") fire against any attackers who should reach the base of any of the walls. The indentations in the base of each point on the star sheltered cannons. Those cannons would have a clear line of fire directly down the edge of the neighboring points, while their point of the star was protected by fire from the base of those points.
Thus forts evolved complex shapes that allowed defensive batteries of cannons to command interlocking
fields of fireThe field of fire of a weapon is the area around it that it can easily and effectively reached by gunfire. The term field of fire is mostly used in reference to machine guns. Their fields of fire incorporate the beaten zone....
. Forward
batteriesIn military organizations, an artillery battery is a unit of guns, mortars, rockets or missiles so grouped in order to facilitate better battlefield communication and command and control, as well as to provide dispersion for its constituent gunnery crews and their systems...
commanded the slopes which defended walls deeper in the complex from direct fire. The defending cannons were not simply intended to deal with attempts to storm the walls, but to actively challenge attacking cannons, and deny them approach close enough to the fort to engage in direct fire against the vulnerable walls.
The key to the fort's defense moved to the outer edge of the ditch surrounding the fort, known as the covered way, or covert way. Defenders could move relatively safely in the cover of the ditch, and could engage in active counter measures to keep control of the
glacisA glacis in military engineering is an artificial slope of earth used in late European fortresses so constructed as to keep any potential assailant under the fire of the defenders until the last possible moment...
, the open slope that lay outside the ditch, by creating defensive earthworks to deny the enemy access to the glacis and thus to firing points that could bear directly on to the walls, and by digging counter mines to intercept and disrupt attempts to mine the fort walls.
Compared to
medieval fortificationMedieval fortification is the military aspect of Medieval technology that covers the development of fortification construction and use in Europe roughly from the fall of the Western Roman Empire to the Renaissance...
s, forts became both lower and larger in area, providing
defense in depthDefence in depth may refer to:*Defence in depth, a military strategy for defense*Defense in Depth , an Information Assurance strategy for computer security...
, with tiers of defenses that an attacker needed to overcome in order to bring cannons to bear on the inner layers of defenses.
Firing emplacements for defending cannons were heavily defended from bombardment by external fire, but open towards the inside of the fort, both to diminish their usefulness to the attacker should they be overcome, but also to allow the large volumes of smoke that the defending cannons would generate to dissipate.
Fortifications of this type continued to be effective while the attackers were armed only with cannons, where the majority of the damage inflicted was caused by momentum from the impact of solid shot. While only low explosives such as black powder were available, explosive shells were largely ineffective against such fortifications.
The development of
mortarsA mortar is a muzzle-loading indirect fire weapon that fires shells at low velocities, short ranges, and high-arcing ballistic trajectories. It typically has a barrel length less than 15 times its caliber.- Function :...
, high explosives, and the consequent large increase in the destructive power of explosive shells and thus plunging fire rendered the intricate geometry of such fortifications irrelevant. Warfare was to become more mobile. It took, however, many years to abandon the old fortress-thinking.
Construction
Due to the massive expense of constructing these new fortifications, they were often improvised from earlier defenses. Medieval curtain walls were torn down and a ditch was dug in front of them. The earth used from the excavation was piled behind the walls to create a solid structure. While purpose-built fortifications would often have a brick fascia because of the material's ability to absorb the shock of artillery fire, many improvised defenses cut costs by leaving this stage out and instead opted for more earth. Improvisation could also consist of lowering medieval round towers and infilling them with earth to strengthen the structures.
It was also often necessary to widen and deepen the ditch outside the walls to create a more effective barrier to frontal assault and mining. Engineers from the 1520s were also building massive, gently sloping banks of earth called
glacisA glacis in military engineering is an artificial slope of earth used in late European fortresses so constructed as to keep any potential assailant under the fire of the defenders until the last possible moment...
in front of ditches so that the walls were almost totally hidden from horizontal artillery fire. The main benefit of the glacis was to deny enemy artillery the ability to fire point blank. The higher the angle of elevation, the lower the stopping power.
An example of the great expense of updating fortifications is the city of
SienaSiena is a city in Tuscany, Italy. It is the capital of the province of Siena.The historic centre of Siena has been declared by UNESCO a World Heritage Site.- History :...
, which went bankrupt in 1544 attempting to update its city walls.
Notable instances
The first key instance of
trace italienne was at the
PapalThe Papal States, State of the Church or Pontifical States were one of the major historical states of Italy from roughly the 6th century until the Italian peninsula was unified in 1861 by the Kingdom of Piedmont-Sardinia .The Papal States comprised territories under...
port of
CivitavecchiaCivitavecchia is a town and comune of the province of Rome in the central Italian region of Latium. A sea port on the Tyrrhenian Sea, it is located 80 kilometers west-north-west of Rome, across the Mignone river...
, where the original walls were lowered and thickened because the stone tended to shatter under bombardment.
The first major battle which truly showed the effectiveness of
trace italienne was the defense of
PisaPisa is a city in Tuscany, central Italy, on the right bank of the mouth of the Arno River on the Ligurian Sea. It is the capital city of the Province of Pisa...
in 1500 against a combined Florentine and
FrenchFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
army. The original medieval fortifications beginning to crumble to French cannon fire, the Pisans constructed an earthen rampart behind the threatened sector. It was discovered that the sloping earthen
rampartA defensive wall is a fortification used to defend a city or settlement from potential aggressors. In ancient to modern times, they were used to enclose settlements...
could be defended against
escaladeEscalade is the act of scaling defensive walls or ramparts with the aid of ladders, and was a prominent feature of siege warfare in medieval times...
and was also much more resistant to cannon fire than the
curtain wallA curtain wall is a type of defensive wall forming part of the defences of some medieval castles.The curtain wall surrounded and protected the interior courtyard, or bailey, of a castle...
it had replaced.
The second siege was that of
PaduaPadua is a city in the Veneto, northern Italy. It is the capital of the province of Padua and the economic and communications hub of the area. Padua's population is 212,500 . The city is sometimes included, with Venice , in the Padua-Venice Metropolitan Area, having a population of c...
in 1509. A monk engineer named Fra Giocondo, trusted with the defense of the
VenetianThe Most Serene Republic of Venice or Venetian Republic was a state originating from the city of Venice in Northeastern Italy. It existed for over a millennium, from the late 7th century AD until the year 1797...
city, cut down the city's medieval wall and surrounded the city in a broad
ditchA ditch is a narrow channel dug in the earth. In military engineering and fortification, a ditch is an obstacle, designed to slow down or break up an attacking force, while a trench is intended to provide cover to the defenders.- Uses :...
that could be swept by flanking fire from gunports set low in projections extending into the ditch. Finding that their cannon fire made little impression on these low ramparts, the French and allied besiegers made several bloody and fruitless assaults and then withdrew.
Effectiveness
According to
Geoffrey ParkerNoel Geoffrey Parker is a leading expert on military history. His best known book is Military Revolution: Military Innovation and the Rise of the West, 1500-1800, first published by Cambridge University Press in 1988. He holds his BA, MA, Ph.D. and Litt.D...
in his article
The military revolution 1560–1660: a myth?, the appearance of the
trace italienne in early modern Europe, and the difficulty of taking such fortifications, resulted in a profound change in military strategy. "Wars became a series of protracted sieges", Parker suggests, and open-pitch battles became "irrelevant" in regions where the
trace italienne existed. Ultimately, Parker argues, "military geography", in other words the existence or absence of the
trace italienne in a given area, shaped military strategy in the early modern period. This is a profound alteration of the military revolution thesis originally proposed by
Michael RobertsMichael Roberts was an English historian specializing in the early modern period and particularly known for his studies of Swedish history.Roberts was born in Lytham St Annes, Lancashire and educated at Brighton College...
in his inaugural lecture delivered at the Queen's University Belfast, in 1955.
See also
- List of star forts
- List of established military terms
- Crenellation
- Menno van Coehoorn
Menno, baron van Coehoorn , was a Dutch soldier and military engineer of Swedish extraction. He made a number of influential weaponry innovations in siege warfare and fortification techniques...
- Vauban
Sébastien Le Prestre, Seigneur de Vauban and later Marquis de Vauban , commonly referred to as Vauban, was a Marshal of France and the foremost military engineer of his age, famed for his skill in both designing fortifications and in breaking through them...
External links