The nephew of Napoleon I, Louis Napoleon spent his youth with his mother, Hortense de Beauharnais, in Switzerland and Germany and became a captain in the Swiss army. Animated by a mixture of liberalism and Bonapartism, he indulged (1830-31) in revolutionary activities in Italy. In 1836 he attempted a ludicrous military coup at Strasbourg and was exiled to the United States by the government of Louis Philippe. He managed to return to Switzerland, but French protests at his proximity finally caused him to depart (1838) for England.
In 1840 he again attempted an insurrection, this time at Boulogne-sur-Mer. He was tried and sentenced to life imprisonment. Detained in the fortress of Ham, Somme department, he wrote letters, pamphlets, and books, among them a mildly socialistic work on the extinction of pauperism. He made an easy escape in 1846, walking out disguised as a laborer, and went to England.
After the February Revolution of 1848 Louis Napoleon returned to France. He gathered a following, was elected to the national assembly, and in Dec., 1848, defeated Louis Eugène Cavaignac in the presidential elections by an overwhelming majority. Although assisted by Cavaignac's unpopularity with the working classes, Louis Napoleon's success was largely due to his name. He vaguely promised support to all interests, and he evoked French nostalgia for past Napoleonic glory. As president of the Second Republic, he was limited by law to one term. He soon began to strengthen his position and took special care to conciliate the powerful conservative forces. The strong Roman Catholic opposition was allayed by allowing (1849) a French army to restore Pope Pius IX to Rome and by assenting (1850) to an education bill, presented by Frédéric de Falloux, which greatly favored the church.
After the defeat in the assembly in July, 1851, of a constitutional amendment that would have allowed the president to serve for more than one term, Louis Napoleon began plans for a coup. The masterly coup of Dec. 2, 1851, was largely engineered by Louis Napoleon's half brother, the duc de Morny. The legislative assembly was dissolved and its meeting place occupied by the army, universal suffrage was established, and a plebiscite authorizing the revision of the constitution was announced. An attempted uprising was brutally repressed. To assure a majority in the plebiscite Morny used tactics of intimidation and strict electoral management.
Victory would, in any case, have been the probable outcome. The Bonaparte name promised glory, order, and a possible solution of France's political division. The plebiscite registered overwhelming approval. The new constitution (Jan., 1852) gave the president dictatorial powers and created a council of state, a senate, and a legislative assembly subservient to the president. Subsequent decrees barred republicans from the ballot and throttled the press.
In Nov., 1852, a new plebiscite overwhelmingly approved the establishment of the Second Empire, and Louis Napoleon became Emperor Napoleon III. For eight years he continued to exercise dictatorial rule, tempered by rapid material progress. Railway building was encouraged; the rebuilding of Paris and other cities brought a construction boom; and the first French investment banks were authorized. Napoleon's foreign ventures were successful at first. The Crimean War (1854-56) and the Congress of Paris (see Paris, Congress of) restored French leadership on the Continent.
Napoleon then turned toward Italy. A long-time supporter of Italian nationalism, he met the Sardinian premier Camillo Cavour at Plombières and secretly agreed on a joint campaign by France and Sardinia to expel Austria from Italy and to establish an Italian federation of four states under the presidency of the pope; France was to be compensated with Nice and Savoy. War broke out in 1859 (see Risorgimento). However, after the costly victory of the French and Sardinians at Solferino, Napoleon suddenly deserted his Italian ally and made a separate peace with Austria at Villafranca di Verona. His act was partly motivated by the opposition of the French clerical party to a policy threatening the independence of the papacy at Rome.
Having lost much popularity, the emperor inaugurated a more liberal domestic policy, widening the powers of the legislative assembly and lifting many restrictions on civil liberties. During the "Liberal Empire" (1860-70) such opposition leaders as Jules Favre, Émile Ollivier, and Adolphe Thiers were outstanding figures. A commercial treaty (1860) with Great Britain opened France to free trade and improved Franco-British relations. Imperialistic expansion was pushed by the French-British expedition (1857-60) against China, the acquisition of Cochin China, and the construction of the Suez Canal. Less fortunate was Napoleon's intervention (1861-67) in the affairs of Mexico; the French troops finally withdrew upon the demand of the United States, leaving Emperor Maximilian to his fate.
Napoleon remained neutral in the Austro-Prussian War of 1866, underestimating Prussian strength. The rise of Prussia under the leadership of Otto von Bismarck revealed a new rival for European power. To regain prestige Napoleon, at the behest of advisers, took an aggressive stand regarding the candidature of a Hohenzollern prince to the Spanish throne. This gave Bismarck the opportunity to goad Napoleon into war (see Ems dispatch).
The Franco-Prussian War (1870-71) brought ruin to the Second Empire. Napoleon himself took the field, leaving his empress, Eugénie, as regent, but he early devolved his command to Achille Bazaine. He was caught in the disaster of Sedan (Sept. 1, 1870), captured by the Prussians, and declared deposed (Sept. 4) by a bloodless revolution in Paris. Released after the armistice (1871), he went into exile in England, bearing defeat with remarkable dignity. His only son, the prince imperial (see under Bonaparte, family), was killed while serving in the British army.
Napoleon III was a complex figure. He combined traits of genuine idealism and liberalism with authoritarianism and ruthless self-aggrandizement. Although much less impressive than his mighty uncle, he was shrewd enough to capitalize on the Napoleonic image and to govern capably, albeit dictatorially. His downfall came when he encountered the far more canny Bismarck.
See studies of the Second Empire by P. de La Gorce (7 vol., 1894-1905, in French), E. Ollivier (18 vol., 1895-1918, in French), P. Guedalla (2d ed. 1928), and J. M. Thompson (1954, repr. 1967); F. A. Simpson, The Rise of Louis Napoleon (new ed. 1925, repr. 1968) and Louis Napoleon and the Recovery of France (3d ed. 1951); A. Guérard, Napoleon III (1943); D. H. Pinkney, Napoleon III and the Rebuilding of Paris (1958); J. P. T. Bury, Napoleon III and the Second Empire (1964); B. D. Gooch, The Reign of Napoleon III (1969); W. H. C. Smith, Napoleon III (1972).