His grandson Louis IX, renowned for his extreme piety (and later canonised as St Louis) established the city as a major centre of pilgrimage in the 13th century with the construction of the cathedral of Notre Dame de Paris, the Basilica of St Denis and the Sainte-Chapelle on the Ile de la Cité. The latter was one of the finest medieval Gothic religious buildings ever constructed and was built to house Louis' most precious possession - the (alleged) Crown of Thorns, purchased from the bankrupt Byzantine Empire at an extortionate price.
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.
Paris is served by two principal airports: Orly Airport, which is south of Paris, and the Charles De Gaulle International Airport in nearby Roissy-en-France. A third and much smaller airport, at the town of Beauvais, 70km (45 miles) to the north of the city, is used by charter and low-cost airlines. Le Bourget airport nowadays only hosts business jets, air trade shows and the aerospace museum.
The Bois de Boulogne and the Bois de Vincennes were both transformed into large public parks. Although Haussmann was forced to resign in 1869 after financial irregularities, his scheme is largely responsible for the present-day look and layout of Paris.
Roman rule in northern Gaul effectively collapsed in the 5th century. In 451 the region was invaded by Attila the Hun, prompting fears that Paris would be attacked. According to legend, the city was saved by the piety of Sainte Geneviève and her followers, whose prayers for relief were answered when Attila's march turned away from Paris to the south. Ste Geneviève remains Paris' patron saint to this day.
Napoleon's rule came to an abrupt end when he declared war on Prussia in 1870, only to be defeated and captured at Sedan. He abdicated on 4 September, with a Third Republic proclaimed that same day in Paris. On 19 September the Prussian army arrived at Paris and besieged the city. Major city landmarks were pressed into military service, with the Louvre being turned into an arms factory, the Gare d'Orleans (now the Gare d'Austerlitz) into a balloon workshop and the Gare de Lyon into a cannon foundry.
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.
Prior to 1968, département 75 was the Seine département, which contained the city of Paris and its immediate suburbs. The splitting up of the Seine département resulted in the creation of four new départements: Paris proper (75), and three départements (Hauts-de-Seine, Seine-Saint-Denis and Val-de-Marne) forming a ring around Paris, often called la petite couronne (i.e. the "small ring", as opposed to the "large ring" of the more distant suburbs of Paris).
The following month, more than 2,000 people were massacred in Paris as revolutionary mobs hunted down and killed anyone seen as an opponent of the new order. The monarchy was formally abolished on 22 September 1792, "Day I of Year I of the French Republic."
The persecution of Jews in Paris began within 48 hours of the city's fall, when they were required to register with police. On 14 May 1941 the Vichy police began deporting Parisian Jews, rounding them up at the Velodrome d'Hiver.
In March 2001, Paris voted for a left-wing mayor for the first time since 1871. Bertrand Delanoë made history not only as the first left-wing mayor for 130 years, but for the fact that he is the first openly gay man to hold such a high public position in France. His election was widely seen as a rejection by the electorate of the corruption of the Chirac era. His manifesto promised to tackle the city administration's corruption and inefficiency, as well as reducing crime and improving education - all while keeping taxation stable.
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.
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 city was neglected by the Empire and suffered grievously from Viking raiders who repeatedly sailed upriver to attack it. On March 28, 845 Paris was sacked by Viking raiders, probably under Ragnar Lodbrok, who collected a huge ransom in exchange for leaving. The weakness of the late Carolingian kings led to the gradual rise in power of the Counts of Paris.
Lutetia was a prosperous place and occupied a very strategic position on the river, controlling shipping in both directions. It came under Roman control after the revolt of 52 BC when Vercingetorix led a Celtic uprising against the Romans under Caesar.