The most striking feature of the city is the Duomo, the large, white-marble cathedral (1386-1813), which shows traces of many styles (especially Gothic). It is elaborately ornamented, with 135 pinnacles and more than 200 marble statues. A statue of the Madonna is on the highest pinnacle (354 ft/108 m). Other points of interest in Milan include Brera Palace and Picture Gallery (17th cent.), which includes major works by Mantegna, Bellini, Piero della Francesca, and Raphael; the Castello Sforzesco (15th cent., with 19th-century additions), which houses a museum of art; the Church of Santa Maria delle Grazie (1465-90), containing the famous fresco, the Last Supper, by Leonardo da Vinci; the Basilica of Sant' Ambrogio (founded in the 4th cent., rebuilt in the 11th-12th cent.); the Ambrosian Library, which houses a rich collection of paintings; the Church of Sant' Eustorgio (9th cent.); the Leonardo da Vinci Museum of Science and Technology; the gallery of modern art; and the Poldi Pezzoli Museum, with paintings by Boticelli, Pollaiuolo, Mantegna, and Piero della Francesca. Long a center of music, Milan has a conservatory and a famous opera house, Teatro alla Scala (opened in 1778). Between the Duomo and La Scala is the 130-year-old Galleria, an enclosed four-story glass-roofed arcade that contains shops and eateries and is a popular gathering place. The city also has three universities and a polytechnic institute.
Probably of Celtic origin, Milan was conquered by Rome in 222 B.C. In later Roman times it was the capital (A.D. 305-402) of the Western Empire and the religious center of N Italy. In 313 Constantine I issued the Edict of Milan, which granted religious toleration. From 374 to 379 the city's bishop was St. Ambrose, known for the liturgy he wrote and for his eloquence. Milan was severely damaged by the Huns (c.450) and again by the Goths (539) and was conquered by the Lombards in 569.
In the 12th cent. it became a free commune and gradually gained supremacy over the cities of Lombardy. From the 11th to the 13th cent. Milan suffered from internal warfare between rich and poor, from the Guelph and Ghibelline strife, and from the enmity of rival cities, which assisted Emperor Frederick I in destroying it (1163). As a member of the Lombard League, Milan later contributed to the defeat of Frederick I at Legnano (1176). The city's independence was recognized in the Peace of Constance (1183). In the 13th cent. Milan lost its republican liberties; first the Torriani, then the Visconti (1277) became its lords. Galeazzo Visconti received (1395) the title of duke of Milan from the emperor, and under him the duchy became one of the most important states in Italy. After the death of the last Visconti (1447) the Sforza became dukes of Milan. The city flourished until it became involved in the Italian Wars and passed under Spanish domination (1535).
At the end of the War of the Spanish Succession, Austrian rule of Milan was established (1713-96). Napoleon I made the city the capital of the Cisalpine Republic (1797) and of the kingdom of Italy (1805-14). In 1815 Milan again came under Austria. It was a leading center throughout the Risorgimento; after five days of heroic fighting in 1848 the citizens of Milan succeeded in expelling the Austrians, who returned, however, a few months later. In 1859 the city was united with the kingdom of Sardinia. Its industrial importance grew after it was incorporated (1861) into Italy. In World War II Milan suffered widespread damage from Allied air raids; many significant buildings were damaged beyond repair.