The historical nucleus of Paris is the Ile de la Cité, a small island largely occupied by the huge Palais de Justice and the Cathedral of Notre-Dame de Paris. It is connected with the smaller Ile Saint-Louis, occupied by elegant houses built in the 17th and 18th centuries. A major characteristic of Paris is its tree-lined quays along the Seine River, in particular, along the Left Bank with its open-air bookstalls, the historic bridges that span the river, and the vast tree-lined boulevards like the Champs-Élysées.
Paris was occupied by a Gallic tribe until the Romans arrived in 52 BC. The invaders referred to the previous occupants the Parisii, but called their new city Lutetia, meaning "marshy place". About fifty years later the city had spread to the left bank of the Seine, now known as the Latin Quarter, and had been renamed "Paris".
Roman rule was over by 508, when Clovis the Frank made the city the capital of the Merovingian dynasty of the Franks. Viking invasions during the 800s forced the Parisians to build a fortress on the Ile de la Cité. During one invasion Paris was sacked by Viking raiders, probably under Ragnar Lodbrok, who collected a huge ransom in exchange for leaving on March 27, 845. The first French king, Odo, was chosen in this period.
During the 11th century the city spread to the Right Bank. The 12th and 13th centuries, which included the reign of Philip II Augustus (1180-1223), are especially notable for the growth of the city. Main thoroughfares were paved, the first Louvre was built as a fortress, and several churches, including the Cathedral of Notre-Dame, were constructed or begun. Several schools on the Left Bank were organized into the Sorbonne, which counts Albertus Magnus and St. Thomas Aquinas among its early scholars. In the Middle Ages Paris prospered as a trading and intellectual centre, interrupted temporarily when the Black Death struck in the 14th century. Under the reign of King Louis XIV, the Sun King, from 1643 to 1715, the royal residence was moved from Paris to nearby Versailles.
The French Revolution began with the storming of the Bastille on July 14, 1789. Many of the conflicts in the next few years were between Paris and the outlying rural areas of France.
In 1870 the Franco-Prussian War ended in a siege of Paris and the Paris Commune, which surrendered in 1871 after a winter of famine and bloodshed. The Eiffel Tower, the best-known landmark in Paris, was built in 1889 in a period of prosperity known as La Belle Époque ("The Age of Beauty).