The area of modern Paris has been inhabited since at least the fourth millennium BC, although little is known about these early inhabitants. The first known permanent settlement on the site was founded about 250 BC by a Celtic tribe called the Parisii, who established a fishing village on the Seine island that was later to become the Ile de la Cité. This was known as Lutetia, a name first recorded by Julius Caesar in his Gallic Wars.
Fierce fighting broke out a few days later as government troops retook the city district by district. It only ended on 29 March, by which time an estimated 4,000-5,000 people on both sides had been killed. In the aftermath, another 10,000 Communards were shot, 40,000 were arrested and 5,000 were deported.
Algeria gained its independence in 1962 and over 700,000 French colonists and pro-French Algerians migrated to the mother country, many to Paris. In response, the government built huge new residential suburbs - the now-notorious banlieues of Paris - which rapidly gained a reputation for soulless architecture, deprivation, racial tension and crime.
A revolt broke out on 18 March when government forces were driven out of Montmartre. The government regrouped at Versailles, while on 26 March the Commune of Paris - effectively a miniature socialist republic - was proclaimed in the city.
The river Seine is well known for its tree-lined quais (walks along the river banks), open-air bookstalls and historic bridges that connect the Right and Left banks. Paris is also famous for its tree-lined boulevards such as the Champs-Élysées, and for its many architectural gems.
In 1900 Paris hosted the 1900 Summer Olympics. In late August 1944 after the battle of Normandy, Paris was liberated when the German general Dietrich von Choltitz surrendered after skirmishes to the French 2nd Armoured Division commanded by Philippe de Hauteclocque backed by the Allies.
As an exception to the normal rules for French cities, some powers normally vested in the mayor of the city are instead vested in a representative of the national government, the Prefecture of Police which also controls the Paris Fire Brigade. As an example, Paris has no municipal police force, though it has some traffic wardens. This is a legacy of the situation that up to 1977, Paris had no mayor and was essentially run by the prefectoral administration.
An invading Prussian army heading for Paris was defeated shortly afterwards, clearing the way for the bloodiest phase of the Revolution. A guillotine was erected in what is now the Place de la Concorde and was used on 21 January 1793 to execute Louis XVI. Marie Antoinette followed in October 1793.
Although the Third Republic was widely disliked for its political instability and corruption, it did manage to deliver a golden age - a belle epoque - for Paris. The city acquired many distinctive new monuments and public buildings, foremost among them the Eiffel Tower, constructed for the World Exhibition of 1889. It was renowned as a centre for the arts, with the Impressionists taking their inspiration from its new vistas.
Paris is densely covered by a metro system, the Métro, as well as by a large number of bus lines. This interconnects with a high-speed regional network, the RER, and also the train network: commuter lines, national train lines, and the TGV (or derivatives like Thalys or Eurostar for specific destinations). There are two tangential tramway lines in the suburbs: Line T1 runs from Saint-Denis to Noisy-le-Sec, line T2 runs from La Défense to Issy. A third line along the southern orbital road is currently under construction.
France's political divisions were a major factor in its ill-preparedness for the outbreak of the Second World War on 3 September 1939. Some of the Catholic Right were openly hostile to parliamentary democracy, Socialism and Communism, and welcomed the possibility of a fascist regime, even imposed by foreign forces.
Less positively and very controversially, the ancient market at Les Halles was demolished and replaced with a notoriously ugly underground shopping mall, and the 209m Tour Montparnasse skyscraper was built leading to fears that Paris would become overrun with American-style skyscrapers (a move strongly resisted ever since).
As early as the 12th century, the distinctive character of the city's districts was emerging. The Ile de la Cité, on which the Cathedral of Notre Dame de Paris was built in 1163, was the centre of government and religious life; the Left Bank was the centre of learning, focusing on the various Church-run schools established there; and the Right Bank was the centre of commerce and finance. A league of merchants, the so-called Hanse Parisienne, was established and quickly became a powerful force in the city's affairs.
The Louvre was redeveloped and acquired its spectacular glass pyramid, while a futuristic new district was constructed just outside the city limits at La Defense. The Opéra Bastille and Bibliotheque Nationale de France François Mitterrand proved less successful, experiencing big cost overruns and a series of technical problems.