During this time, it was successively a Celtic oppidum, an important Gallo-Roman city,[2] the Merovingian capital of the Austrasia kingdom,[3] the birthplace of the Carolingian dynasty,[4] a cradle of Gregorian chant,[5] and one of the oldest republics of the common era in Europe.
[7] The city had one of the largest amphitheatres in Gaul,[2][10] and an aqueduct of 23 km (14.29 mi) and 118 arches, extending from Gorze to Metz, was constructed in the 2nd century AD to supply the thermae with water.
[11] Remains of the aqueduct may still be seen today, notably in the cities of Jouy-aux-Arches and Ars-sur-Moselle,[11] and the vestiges of the thermae can be visited in the basement of the Golden Courtyard museum.
After converting the local inhabitants to Christianity after they agreed to do so in return for ridding them of the dragon, Clement went into the amphitheater and quickly made the sign of the cross after the snakes attacked him.
[3] When the Carolingians acceded to the Frankish throne, the town retained their goodwill as it had long been a base of their family and their primal ancestors; Saint Arnuff and Chlodulf had been bishops of Metz.
[20] A group of crusaders entered Metz and forced the sizeable Jewish community of the city to convert to Catholicism, killing 22 people who refused baptism.
[5] Gregorian chant was created in Metz during the 8th century as a fusion of Gallican and ancient Roman repertory, and remains the oldest form of music still use in Western Europe.
Then called Messin Chant, the bishops of Metz, notably Saint-Chrodegang, promoted its use for the Roman liturgy in Gallic lands in the favorable atmosphere of Carolingian monarchs.
[6] The Republic of Metz was organized around three legislature: the Head-Alderman representing the city, a comity of 13 aldermen acting as Lay community counsellors, and a House of Burgesses giving its opinion.
[25] Emperor Charles IV in 1354 and 1356 held diets in Metz, where the Golden Bull decree of 1356 was promulgated, fixing important constitutional aspects of the Holy Roman Empire.
[28] Emperor Charles V, during the Italian War of 1551–1559, made an attempt to regain overlordship of Metz by force of arms, besieging the city in 1552–1553.
[29] A bridge castle from the 13th century, the Porte des allemands (German Gate), which played a crucial defensive role during the siege, is still visible today, and bullet impacts from the muskets used during the assaults can be seen on its facade.
Belle-Isle awarded royal architect Jacques-François Blondel in 1755 for the embellishment of the town square and the construction of the Hôtel de Ville (city hall),[31][32] the parliament, and lodgings for the guard.
Also, future revolutionary leader Maximilien de Robespierre and abolitionist Abbé Grégoire were decorated by the National Academy of Metz in 1784 and 1787 respectively, for their essays on capital punishment and in favour of the education of underprivileged people and religious tolerance.
[7] General François Christophe Kellermann led the local Army of the Moselle during the French Revolutionary Wars, notably at the decisive Battle of Valmy against the Prussian troops.
[7] Later, Metz was besieged by the Sixth Coalition during the campaign of 1814 against Napoleonic France, but the Allies were unable to take the city defended by General Pierre François Joseph Durutte and his army.
[36] In 1861, during the Second French Empire, Metz hosted the fourth universal world's fair in the Place de la république and the Esplanade gardens.
[39] The first airmail carrier was launched during the siege of the city by Doctor Julien-François Jeannel with the help of some officers of the Imperial Guard near the present-day France's square.
The urban architects, under the direct guidance of Emperor Wilhelm II, had to respond to two major challenges in planning the new district: the requirement of the military strategies and the erection of a functional and artistic ensemble.
Indeed, the army required a well-planned district built with the prospect of a war between Germany and France in mind and strategically integrated to the Schlieffen plan.
Later, Pope John Paul II delivered a Mass in the Saint-Stephen Cathedral during his visit to Metz in 1988 and pleaded in his speech for the European unity in the context of the Cold War.