Grand Uniform of the École Polytechnique
The history of the Grand Uniform of the École Polytechnique reflects numerous changes, modeled on the shifts in political regimes, successive governments, and wars that have shaped France's history since the late 18th century. From the National Convention to the Fifth Republic, the Grand Uniform reflects the evolution of societal organization.
Originally, polytechnic students were issued two uniforms: one for daily use, known as "BD" for Battle Dress in the 20th century, and the other, a ceremonial uniform called "grande tenue," which over time became known as the Grand Uniform. The interior uniform should not be confused with the "petite tenue" or Petit Uniforme, a formal dress similar to the Grand Uniform except for the headgear.
Although the interior uniform disappeared in the 20th century, the Grand Uniform has endured. Every student, called an "X," receives a Grand Uniform—commonly referred to as "GU," pronounced gy in —which is worn for military ceremonies and specific events linked to the École Polytechnique, such as the.
Since its creation in 1794, wearing the uniform has been a tradition that unites all generations of students who have passed through the École Polytechnique. It symbolizes belonging to a community that claims a heritage of over two centuries.
History
First Republic and First Empire
The French Revolution of 1789 led to the abolition of many French institutions and a disruption of social norms, including the uniforms of royal armies. In this context, the École Centrale des Travaux Publics, which would be renamed École Polytechnique a year later, was established on 21 Ventôse Year II to provide the nation with high-level leaders on a meritocratic model and to contribute to the war effort through knowledge and technical skills during the French Revolutionary Wars.On 6 Frimaire Year III, a few months after the school's creation by the National Convention,, the school's first director-general, proposed issuing uniforms to students despite their civilian status. The objective was to distinguish polytechnicians from other citizens while instilling respect for the uniform. On 8 Pluviôse Year IV, the uniform of a cannoneer of the National Guard was assigned to students—a tricolor cockaded hat, gold buttons, and a saber. However, implementing the decree in a turbulent political context proved challenging. The École Centrale des Travaux Publics was renamed École Polytechnique by the law of 15 Fructidor Year III, and it was on the 1796 class uniform that the buttons bore the inscription "École Polytechnique" for the first time.
The coup d'état of 18 Fructidor, Year V (September 4, 1797), saw three members of the Directory, supported by the army, overthrow the Council of Five Hundred and the Council of Ancients, which were controlled by a royalist majority. The legislative body's guard offered no resistance, but the polytechnicians showed readiness to intervene in defense of the legislative power if the conflict turned violent. The incident at the Théâtre des Jeunes-Artistes, where students instigated violent altercations, convinced the ruling authorities to find a way to temper the students' behavior. In 1798, a formal decision ordered them to obtain a uniform without delay, as it was believed that, once identifiable, they would exhibit more restrained behavior. The new uniform consisted of a shawl-collared coat closed by five gold buttons, cut in the French style, with a jacket and trousers in national blue, and a three-cornered hat. More civilian than military in appearance, it was said to have been inspired by the designs of David.
The tricorne had the drawback of hindering the handling of the rifle: the front horn made it difficult to hold the weapon vertically and obstructed the wearer's field of vision. This third horn gradually disappeared, leading to adopt the bicorne worn en bataille, a headgear generalized across all regiments between 1786 and 1791. While the tricorne was associated with the Ancien Régime, the bicorne, on the contrary, became a symbol of republican identity.
A uniform for both full dress and undress, in the infantry style, was assigned to the students when Napoleon I granted the École its by the decree of 27 Messidor, Year XII. This decision had a dual objective: on the one hand, to bring disorderly students under control, particularly through barracks discipline, as their behavior could pose a threat to political authority; and on the other hand, to anticipate the needs of the Napoleonic army.
Under the First Empire, the shako replaced the tricorne and bicorne throughout the Napoleonic infantry: this hardened headgear provided better protection for soldiers. Around 1809, according to, this visor-capped headgear was thus given to the students of the École, who also retained the bicorne due to their vocation to serve in the scientific branches—engineering, artillery—which were not expected to be in direct contact with the enemy. Serving in the scientific branches did not prevent the polytechnicians from distinguishing themselves in 1814 during the defense of Paris against the European allied forces opposing Napoleon I. Chateaubriand mentions this feat of arms in his Mémoires d'outre-tombe:
From the Restoration to the Second Empire
During the [Bourbon Bourbon Restoration in France|Restoration in France|Restoration], the École was sanctioned for insubordination, with the principal troublemaker being Auguste Comte. This resulted in a collective dismissal on April 13, 1816. This event foreshadowed the reorganization ordinance of September 4, 1816, under Louis XVIII, which abolished the military regime and apparatus of the École. Consequently, the military uniform was replaced by civilian attire, including a top hat.In 1822, the École Polytechnique was repeatedly disturbed by internal unrest. The students had developed the habit of submitting collective decisions to a vote, which caused disorder in the monarchical context. One student was expelled; out of solidarity, all his classmates declared their intention to leave as well. The conflict was eventually resolved through the erosion of collective solidarity, but following this crisis, the civilian regime was called into question. Thus, following the royal ordinances of September 17 and October 20, 1822, under Louis XVIII, General Bordessoulle, then governor of the École, once again provided the students with a military uniform: polytechnicians wore the frock coat but, above all, resumed wearing the bicorne, with the sergeants carrying a sword.
On July 25, 1830, the Ordinances of Saint-Cloud issued by Charles X suspended the freedom of the press, sparking the revolution in Paris. Following the Three Glorious Days, all the students were granted the right to carry a sword in recognition of their role in defending liberties alongside the insurgent people on the barricades. The presence of a polytechnician in the background of the painting Liberty Leading the People is a testament to the Nation's recognition of the support provided by the polytechnicians to the insurgents of 1830. Thus, the polytechnicians, who already had used the saber, obtained the sword in 1830, which they called the "tangent."
The Marquis de Lafayette expressed the :
After 1824 and for a time, some students adopted, without regulatory approval, the Spanish cape known as the manteau à la chiroga, which they wore draped over the shoulder. Wearing the frock coat and the cape was in keeping with the fashion of the time. In particular, this Spanish cape, also called the, originated from the 1823 Spanish expedition led by France, which aimed to restore King Ferdinand VII to the throne and thereby replace the constitutional monarchy of the Liberal Triennium with an absolute monarchy. The liberals, in opposition to the royalists, named their cape after General, who was one of the leaders of the Spanish army's insurrection on the Isle of León, and wore the cape in his manner—draped over the shoulder. The cape gradually lost its political connotation: with fashion's influence, both liberals and royalists wore the same cape, though one was made of crimson velvet and the other of black velvet. The redingote coat later became preferred, completing the small uniform in 1840.
The 1822 uniform, particularly popular, was worn at the École under Louis-Philippe and Napoleon III without modification—except for the removal of fleur-de-lis symbols under the July Monarchy, which eliminated certain monarchical symbols —and remained unchanged until the fall of the Second Empire at the end of the Franco-Prussian War in 1870.
From the Third to the Fifth Republic
France's defeat in the 1870 war led to a sweeping reform of uniforms throughout the military corps. The École Polytechnique was no exception, and from 1874, the frock coat was replaced by a black tunic with two rows of buttons, similar to that of engineering officers. In 1889, the tunic was replaced by a shorter jacket fastened at the chest with seven large uniform buttons. The rounded collar was replaced with a square-cut collar, to which a white inner collar was attached.The Grand Uniform does not appear to have undergone significant changes under the Third Republic, except for the change of the collar insignia, which reverted from two intertwined laurel or olive branches to a grenade starting in 1903.
Starting in 1905, tensions increased between France and Germany over the division of Africa and the control of Morocco; the Tangier Crisis is a notable example of the rivalry between the two powers. In this context of European imperialist rivalry, in 1908, students of military schools were given officer cadet stripes: white alphas adorned with a red border. This measure was linked to the mass assignment of officers to troop units upon graduating from the École Polytechnique. A gold version of these alphas, associated with the rank of candidate, appeared in 1919 when students returned as promoted officers from World War I.
During the Nazi occupation, the École lost its military status; as a result, rank insignia were replaced by laurel branches on the uniforms of students who became civilians. Apart from this exception, the uniform was not modified. A letter from the École's commander to the Minister of War attests that the wearing of alphas was reinstated in 1945 when the École regained its military status. After the class of 1947, polytechnicians no longer had any rank insignia on their uniforms.
Until the mid-20th century, the indoor uniform was called berry referring to the Berry cloth used to make it. After World War II, it was replaced by the "Battle Dress" from British Army uniforms. This indoor uniform, commonly called "B.D.," became unpopular among students in the post-May 1968 anti-militarist and anti-authoritarian context. This sentiment was reflected in multiple "uniform strikes" — in 1972, 1975, and 1977 — initiated by students for various reasons. The class of X1985 finally abolished the indoor uniform, making the Grand Uniform the only uniform for polytechnicians.
The events of May 1968 also led to the temporary or permanent disappearance of many traditions at the École, including the Khômiss and the Code X, a collection of rules and traditions established by the students. In particular, it dictated how to wear the bicorne since 1852:
The expression "mean and extreme ratio" refers to the ideal proportions of the golden ratio. The Khômiss was not reestablished until 1987, and students resumed wearing the bicorne in this manner from that date.
Constitution of the Grand Uniform for military cadres
In a pursuit of uniformity, the decision to equip all officers in leadership roles with a Grand Uniform, and consequently the creation of the bicorne for cadres, was made in 1979. It was worn for the first time during the July 14th parade in 1980. Until then, Army officers wore the so-called "31" outfit with a kepi and saber, featuring a row of gold buttons and made of black cloth; Navy and Air Force officers wore their respective ceremonial uniforms. The Grand Uniform for non-commissioned officers, including the bicorne, dates back to 2003.In 2018, during the departure ceremony for the X2015 class, Director General François Bouchet reintroduced the Grand Uniform for generals, modeled after the uniform worn by generals between 1918 and 1940, demonstrating a commitment to preserving traditions at the École Polytechnique.
Women's Grand Uniform
In 1972, the École Polytechnique entrance exam was opened to women. Consequently, they needed to be provided with a Grand Uniform. The uniform was chosen from several proposals. In his memoirs, Michel Debré claims that the model was selected by his wife. The chosen design was by couturier, who was known for dressing General de Gaulle. The first women's Grand Uniform featured a skirt, pumps, and a tricorne. The original tricorne was crafted based on a model from the Royal Navy. From the 1973 class onward, female polytechnicians received a lower tricorne adorned with a cockade and a cul-de-dé.The original skirt was cut slightly above the knee. recalls: "Our skirt didn't go past the knee, but in the era of miniskirts, it already seemed quite long to us." It was lengthened in 1974 to cover the knee. Legend has it that the wife of, uncomfortable at the sight of the bare knees of female polytechnicians, convinced her husband. The 1974 technical manual thus specified that "the length of the skirt is determined so that the hem stops at mid-knee." Fashion had also changed; as early as 1970, Paris Match headlined "The Miniskirt is Dead." After pumps were replaced by boots, the skirt was lengthened further to cover the exposed part of the leg, and was widened accordingly to allow for marching in step—resulting in an aesthetic outcome that was not universally appreciated.
The first female polytechnicians were denied the right to wear the tangente, a term for the sword, which had become a symbol of the École since 1830. Instead, they were given a black handbag, not used during ceremonies. Starting in 1977, female polytechnicians were finally permitted to wear the tangente and thus wore the sword belt.
The first Grand Uniform for women included pumps. The first ceremony, held on November 11, 1972, took place in cold weather. The female polytechnicians reportedly requested warmer footwear, and from the X1976 class onward, pumps were replaced by boots. Another explanation, supported by uniformology and the simultaneous nature of events, suggests that as soon as the sword was granted to female polytechnicians, the pumps had to be replaced by boots. The first boots were form-fitting and featured a 4 cm, wide, flat heel. A few years later, around 1986, wider boots with a lower, stacked heel were adopted. Around 2000, slim-fitting Paraboot boots with thick soles and zippers were introduced, though they were not universally liked.
The red scrunchie quickly appeared to standardize the hairstyles of young women.
In 1996, female polytechnicians were granted the right to wear the bicorne—an iconic symbol of the École—replacing the tricorne. Representing the X1994 class, Caroline Aigle and Marie Bayrou—the daughter of François Bayrou, then Minister of National Education—advocated for this change in the office of the Director General.
For aesthetic and uniformity reasons, the skirt was replaced by trousers for the 2020 class of female polytechnicians. This choice was also influenced by fashion trends: in 2017, Dior's Spring-Summer collection reinterpreted the women's Grand Uniform with a mandarin collar and trousers.
Polytechnician slang and the Grand Uniform
As demonstrated by the term "tangente," polytechnician slang has embraced the Grand Uniform. The following examples, some of which fell out of use in the 20th century, show that the reverse is also true: the Grand Uniform influenced the slang of the X.Top of the Class: "major de promotion"
The top fifty students in the entrance exam, who served as barracks leaders, were appointed sergeants. The top-ranking student was named sergent-major, which is the origin of the expression "major de promotion." They wore insignia on their uniforms: two diagonal stripes for sergeant-majors and one for sergeants.Foreign students: "constants"
From 1794 until the early 20th century, the few foreign students at the X were considered auditors, not full polytechnicians. As a result, they did not receive the school's uniform and, in particular, were not issued the tangente. This led to a mathematical pun referencing the geometric term "tangent."The term "constant" fell out of use after 1921, when foreign students were admitted to the entrance exam and received the complete uniform.
Courtyard entry, a ''boîte à claque''
The bicorne was cumbersome to carry. For a time, a foldable model existed that could flatten, and the onomatopoeia "clac," mimicking the sound the hat made when folding, earned it the nickname claque. The name stuck even after the foldable model was discontinued.The bicorne was stored in a trapezoidal box resembling the shape of the entrance courtyard of the École at 5 in Paris. As a result, this small courtyard became known as the boîte à claque.
Military service: cuirs and zincs
At the beginning of the 20th century, some students completed their military service in their first year, while others did so in their second year. In 1903, the École considered issuing bronzed steel scabbards to students, replacing the previously used blackened leather scabbards. Consequently, first-year students received leather scabbards, while those who arrived a year later after serving in the troops received metallic scabbards, nicknamed zincs. By metonymy, the term cuirs referred to students who entered the École directly, while zincs referred to those who arrived a year later after military service. For the 1906 to 1912 classes, cuirs were distinguished in the school's directory by the mention "c." The designation gradually faded away as the metallic scabbard was distributed to all students.Red and yellow: origins of class colors
At the École Polytechnique, even-numbered class years are known as rôujes, while odd-numbered years are jônes. This tradition stems from the history of the École's uniform.It dates back to 1823, during the Restoration, when the École regained its military status. Students were issued two hats: the bicorne and the bonnet de police—the first was worn with the Grand Uniform, and the second with the Petit Uniforme.
The bonnet de police was adorned with a tuft of threads. In the French Navy, this tuft evolved into the pompom of the sailor cap, while it became a decorative tassel on the bonnet de police.
In their second year, students transitioned from the red-tasseled bonnet de police to the elegant gold-tasseled cap of non-commissioned officers, marking their promotion to sergeants: "elegant bonnet de police with a golden tassel."
In 1843, polytechnicians were equipped with a kepi. Though they still received a bonnet, they were no longer permitted to leave the École wearing it. This change had two effects on students who paid for their equipment:
- The "gold" tassel was replaced with a less expensive yellow one.
- It became unnecessary to switch caps after the first year.
In 1874, the bonnet de police was permanently replaced by a kepi known as the "small dress" kepi. It was decided that the grenade emblem would alternate between red and yellow depending on the parity of the graduating class. The 1887 regulation established that: "On the front of the band is placed a grenade, embroidered in jonquil yellow wool for students of one division; in scarlet wool for students of the other division, alternating in this manner."
Therefore, the piping on the interior kepi also adopted the color associated with the promotion's class year.