Nancy is the prefecture of the northeastern French department of Meurthe-et-Moselle. It was the capital of the Duchy of Lorraine, which was annexed by France under King Louis XV in 1766 and replaced by a province, with Nancy maintained as capital. Following its rise to prominence in the Age of Enlightenment, it was nicknamed the "capital of Eastern France" in the late 19th century. The metropolitan area of Nancy had a population of 511,257 inhabitants at the 2018 census, making it the 16th-largest functional urban area in France and Lorraine's largest. The population of the city of Nancy proper is 104,885.

The motto of the city is Non inultus premor (Latin for 'I am not injured unavenged')—a reference to the thistle, which is a symbol of Lorraine. Place Stanislas, a large square built between 1752 and 1756 by architect Emmanuel Héré under the direction of Stanislaus I of Poland to link the medieval old town of Nancy and the new city built under Charles III, Duke of Lorraine in the 17th century, is now a UNESCO World Heritage Site, the first square in France to be given this distinction. The city also has many buildings listed as historical monuments and is one of the European centres of Art Nouveau thanks to the École de Nancy. Nancy is also a large university city; with the Centre Hospitalier Régional Universitaire de Brabois, the conurbation is home to one of the main health centres in Europe, renowned for its innovations in surgical robotics.

The earliest signs of human settlement in the area date to 800 BC. Early settlers were likely attracted by easily mined iron ore and a ford in the river Meurthe. Its name is first attested as Nanciaco, possibly from a Gaulish personal name. A small fortified town named Nanciacum (Nancy) was built by Gérard, Duke of Lorraine around 1050.

Nancy was burned in 1218 at the end of the War of Succession of Champagne, and conquered by Emperor Frederick II. It was rebuilt in stone over the next few centuries as it grew in importance as the capital of the Duchy of Lorraine. Duke Charles the Bold of Burgundy, was defeated and killed in the Battle of Nancy in 1477; René II, Duke of Lorraine became the ruler.

• 
  Engraving depicting the capture of Nancy through Duke René II of Lorraine in 1477
• 
  1477 Battle of Nancy

Following the failure of both Emperor Joseph I and Emperor Charles VI to produce a son and heir, the Pragmatic Sanction of 1713 left the throne to the latter's next child. This turned out to be a daughter, Maria Theresa of Austria. In 1736, Emperor Charles arranged her marriage to Duke François of Lorraine, who reluctantly agreed to exchange his ancestral lands for the Grand Duchy of Tuscany.

The exiled Polish king Stanislaus I (Stanisław Leszczyński in Polish), father-in-law of the French king Louis XV, was then given the vacant duchy of Lorraine. Under his nominal rule, Nancy experienced growth and a flowering of Baroque culture and architecture. Stanislaus oversaw the construction of Place Stanislaus, a major square and development connecting the old medieval with a newer part of the city. On the south side of the Place Stanislaus is the Hôtel de Ville, which was completed in 1755. Upon Stanislaus' death in February 1766, Lorraine and Barrois became a regular government of the Kingdom of France. A parlement for Lorraine and Barrois was established in Nancy in 1776.

As unrest surfaced within the French Armed Forces during the French Revolution, a full-scale mutiny, known as the Nancy affair, took place in Nancy in the latter part of summer 1790. A few units loyal to the government laid siege to the town and shot or imprisoned the mutineers.

• 
  Parade in 1909
• 
  Nancy c. 1914
• 
  Nancy in World War I

In 1871, Nancy remained French when Germany annexed Alsace-Lorraine. In 1909 it hosted the Exposition Internationale de l'Est de la France between May and November.

Nancy was occupied by German forces beginning in 1940 and renamed Nanzig. During the Lorraine Campaign of World War II, Nancy was liberated from Nazi Germany by the US Third Army in September 1944, at the Battle of Nancy.

In 1988, Pope John Paul II visited Nancy. In 2005, French President Jacques Chirac, German Chancellor Gerhard Schröder and Polish President Aleksander Kwaśniewski inaugurated the renovated Place Stanislas, which was recognised as a UNESCO World Heritage Site in 1983.

Nancy is situated on the left bank of the river Meurthe, about 10 km upstream from its confluence with the Moselle. The Marne–Rhine Canal runs through the city, parallel to the Meurthe. Nancy is surrounded by hills that are about 150 m higher than the city center, which is situated at 200 m above mean sea level. The area of Nancy proper is relatively small: 15 km. Its built-up area is continuous with those of its adjacent suburbs. The neighboring communes of Nancy are: Jarville-la-Malgrange, Laxou, Malzéville, Maxéville, Saint-Max, Tomblaine, Vandœuvre-lès-Nancy and Villers-lès-Nancy.

The oldest part of Nancy is the quarter Vieille Ville – Léopold, which contains the 14th century Porte de la Craffe, the Palace of the Dukes of Lorraine, the Porte Désilles and the 19th century St-Epvre basilica. Adjacent to its south is the quarter Charles III – Centre Ville, which is the 16th–18th century "new town". This quarter contains the famous Place Stanislas, the Nancy Cathedral, the Opéra national de Lorraine and the main railway station.

The population of the city proper experienced a small decrease in population since 2007, placing it behind Metz as the second largest city in the Lorraine. However, the urban area of Metz experienced population decline from 1990 to 2010 while the urban area of Nancy grew over the same period, becoming the largest urban area in Lorraine and second largest in the "Grand Est" region of northeastern France. Within the Nancy metropolitan area in recent years, the city population declined slightly (2009–2014) at the roughly same time as a small increase in the population of its urban area (2006–2012).

Nancy has an oceanic climate (Köppen: Cfb), although a bit more extreme than most of the larger French cities. By the standards of France it is a "continental" climate with a certain degree of maritime (unrelated to the Köppen classification, since generally the whole country has a predominant mechanism favored by the West winds).

The temperatures have a distinct variation of the temperate zone, both during the day and between seasons but without being very different. Winters are cold and dry in freezing climates. Summers are not always sunny, but warm enough. Mists are frequent in autumn and the winds are light and not too violent. Precipitation tends to be less abundant than in the west of the country. Sunshine hours are almost identical to Paris and the snowy days are the same as Strasbourg (most similar weather conditions). Although the lowest recorded temperature is officially −26.8 °C, some sources consider temperatures from −30 °C on 10 December 1879 before continuous data.

Comparison of local Meteorological data with other cities in France

Town	Sunshine (hours/yr)	Rain (mm/yr)	Snow (days/yr)	Storm (days/yr)	Fog (days/yr)
National average	1,973	770	14	22	40
Nancy	1,666	775.1	29.6	27.6	49.6
Paris	1,661	637	12	18	10
Nice	2,724	767	1	29	1
Strasbourg	1,693	665	29	29	56
Brest	1,605	1,211	7	12	75

Historical population

Year Pop. ±% p.a. 1793 29,141 —     1800 28,227 −0.45% 1806 30,532 +1.32% 1821 29,241 −0.29% 1831 29,122 −0.04% 1836 31,445 +1.55% 1841 35,901 +2.69% 1846 38,795 +1.56% 1851 40,289 +0.76% 1856 48,199 +3.65% 1861 49,305 +0.45% 1872 52,978 +0.66% 1876 66,303 +5.77% 1881 73,225 +2.01% 1886 79,038 +1.54% 1891 87,110 +1.96% 1896 96,306 +2.03% 1901 102,559 +1.27%	Year Pop. ±% p.a. 1906 110,570 +1.52% 1911 119,949 +1.64% 1921 113,226 −0.58% 1926 114,491 +0.22% 1931 120,578 +1.04% 1936 121,301 +0.12% 1946 113,477 −0.66% 1954 124,797 +1.20% 1962 128,677 +0.38% 1968 123,428 −0.69% 1975 107,902 −1.90% 1982 96,317 −1.61% 1990 99,351 +0.39% 1999 103,605 +0.47% 2007 105,349 +0.21% 2012 105,067 −0.05% 2017 104,286 −0.15% 2021 104,260 −0.01%
Graphs are unavailable due to technical issues. Updates on reimplementing the Graph extension, which will be known as the Chart extension, can be found on Phabricator and on MediaWiki.org.
Source: EHESS and INSEE (1968-2021)

The old city center's heritage dates from the Middle Ages to the 18th century. The cathedral of Nancy, the Triumphal Arch and the "Place de la Carrière" are a fine examples of 18th-century architecture. The Palace of the Dukes of Lorraine is the former princely residence of the rulers. The palace houses the Musée Lorrain.

A historic church is the Church of Notre-Dame-de-Bonsecours, Nancy, final resting place of the last duke Stanislas. Other notable churches are the Church of Saint-François-des-Cordeliers and the Basilica of Saint-Epvre, which have historical ties to the ducal House of Lorraine.

The Place Stanislas named after king of Poland, Grand Duke of Lithuania and duke of Lorraine Stanislaus I, Place de la Carrière, and Place d'Alliance were added on the World Heritage Sites list by the UNESCO in 1983.

The "École de Nancy", a group of artists and architects founded by the glassmaster and furniture maker Émile Gallé, worked in the Art Nouveau style at the end of the 19th century and the early 20th century. It was principally their work which made Nancy a center of art and architecture that rivaled Paris and helped give the city the nickname "Capitale de l'Est". The city still possesses many Art Nouveau buildings (mostly banks or private homes). Furniture, glassware, and other pieces of the decorative arts are conserved at the Musée de l'École de Nancy, which is housed in the 1909 villa of Eugène Corbin, a Nancy businessman and supporter of the Art Nouveau there. The Musée des Beaux-Arts has further collections of the Art Nouveau movement.

A major botanical garden, the Jardin botanique du Montet, is located at Villers-lès-Nancy. Other gardens of interest include the city's earliest botanical garden, the Jardin Dominique Alexandre Godron, and various other public gardens and places of interest including the Pépinière and Parc Sainte-Marie (public gardens). The town also has an aquarium. The surroundings of the train station are a busy commercial area.

The city is known for its World Heritage buildings at the Place Stanislas, which was opened April 2005 by Jacques Chirac after refurbishment.

At the turn of the 20th century, Nancy was a major center of the Art Nouveau with the École de Nancy. The city possesses a unique and interesting Musée de l'École de Nancy (School of Nancy Museum) with artworks by Émile Gallé, Louis Majorelle, Daum, Caravaggio, and others. Nancy also has other museums:

• Museum of Fine Arts of Nancy (Musée des Beaux-Arts de Nancy) with painters from the 15th to 20th centuries, and a huge collection of Daum crystal displayed in part of the old fortifications of the city.
• Lorraine History Museum [fr] dedicated to the history of the Duchy of Lorraine and arts (Jacques Callot collection, Georges de La Tour).
• Aquarium and Natural History Museum of Nancy [fr].
• Musée de l'École de Nancy offers a testimony of the diversity of creative techniques practiced by the artists of this school, with a fine display of furniture, objets d'art, glassware, stained-glass, leather, ceramics, textiles, etc. from the period.
• The Iron History Museum

The city is also the seat of the Diocese of Nancy and the home of the Opéra national de Lorraine. There is a network of libraries, the central of which is Bibliothèque municipale de Nancy.

Nancy is known for its macarons and bergamotes, candies flavored with bergamot essential oil.