The so-called port of Barcelona was at first only an open beach, on the east, slightly sheltered by the neighbouring hills, but at an early period the advantage of some artificial protection was felt. In 1438 Don Alphonso V. granted the magistracy a licence to build a mole; and in 1474 the Moll de Santa Creu was officially begun. Long after this, however, travellers speak of Barcelona as destitute of a harbour; and it is only in the 17th century that satisfactory works were undertaken. Until modern times all the included area was shut off from the open sea by a sand-bank, which rendered the entrance of large vessels impossible. An extension of the former mole, and the construction of another from the foot of Montjuich, have embraced a portion of the sea outside of the bank, and a convenient shelter is thus afforded for the heaviest battleships. From 1873 the work of extension and improvement was carried on systematically, with the addition of new quays, greater storage room, and better means for handling cargo. After thirty years of steady development, further plans were approved in 1903. At this time the port included an inner harbour, with a depth of 18 to 30 ft. at low tide, and an outer harbour with a depth of 20 to 35 ft.

In the following year 8075 vessels of nearly 5,000,000 tons entered the port. Barcelona is well supplied with inland communication by rail, and the traffic of its streets is largely facilitated by tramway lines running from the port as far as Grácia and the other chief suburbs.

Barcelona has long been the industrial and commercial centre of eastern Spain - a pre-eminence which dates from the 12th and 13th centuries. It received a temporary check from the disasters of the Spanish-American War of 1898; but less than a year later it paid about £550,000 in industrial and commercial taxes, or more than 11% of the whole amount thus collected in the kingdom; and within five years it had become a port of regular call for thirty-five important shipping companies. It also contained the head offices of thirteen other lines, notably those of the Transatlantic Mail Company, which possessed a fleet of twenty-five fine steamships. Trades and industries give occupation to more than 150,000 hands of both sexes. The spinning and weaving of wool, cotton and silk are the principal industries, but the enterprising spirit of the Catalans has compelled them to try almost every industry in which native capital could attempt to compete with foreign, especially since the institution of the protectionist tariffs of 1892. The native manufacturers are quite able to compete in peninsular markets with foreign rivals. This prosperity has been in part due to the great development of means of communication around the city and in the four Catalan provinces.

Comestibles, raw materials, and combustibles form the greater part of the imports, but this great manufactory also imports a considerable quantity of foreign manufactured goods. The principal exports are wines, cereals, olive-oil, cotton goods, soap, cigarette-paper, furniture and barrels, boots, shoes and leather goods, and machinery.

Barcino, the ancient name of the city, is usually connected with that of the Carthaginian Hamilcar Barca, its traditional founder in the 3rd century B.C. After the Roman conquest, it received from Augustus (27 B.C.-A.D. 14) the name of Julia Faventia (afterwards Augusta and Pia), with the status of a Roman colony; and thenceforward it rapidly grew to be the leading mart of the western Mediterranean, rivalling Tarraco (Tarragona) and Massilia (Marseilles) as early as the 2nd century A.D. As its remains testify, the Roman city occupied Monte Taber. The bishopric of Barcelona was founded in 343. In 415 and 531, the Visigoths chose Barcelona as their temporary capital; in 540 and 599 church councils were held there. Barcinona or Bardjaluna, as it was then called, was captured by the Moors in 713, and in 801 it passed, with the rest of Catalonia, under the dominion of the Franks. From 874 the counts of Barcelona ruled as independent monarchs. But the accession of larger resources due to the union between Catalonia and Aragon in 1149, brought the city to the zenith of its fame and wealth.

Its merchant ships vied with those of Genoa, Venice and Ragusa, trading as far west as the North Sea and the Baltic, and as far east as Alexandria. In 1258 James I. of Aragon empowered Barcelona to issue its famous Consulado del Mar, a code of maritime law recognized as authoritative by many European states. Consuls represented Barcelona at the principal commercial centres on or near the Mediterranean; and the city was among the first communities to adopt the practice of marine insurance. But the union of Castile and Aragon in 1479 favoured other cities of Spain at the expense of Barcelona, whose commercial supremacy was transferred to the ports of western Spain by the discovery of America in 1492. The citizens attributed their misfortunes to the "Castilian" government, and a strong party among them favoured annexation by France. In 1640 Barcelona was the centre of the Catalonian rebellion against Philip IV., and threw itself under French protection. In 1652 it returned to its allegiance, but was captured by the duke of Vendôme in 1697. At the peace of Ryswick, in the same year, it was restored to the Spanish monarchy.

During the War of the Succession (1701-1714) Barcelona adhered to the house of Austria. The seizure of Montjuich in 1705, and the subsequent capture of the city by the earl of Peterborough, formed one of his most brilliant achievements. In 1714 it was taken after an obstinate resistance by the duke of Berwick in the interests of Philip V., and at the close of the war was reluctantly reconciled to the Bourbon dynasty. In 1809 the French invaders of Spain obtained possession of the fortress and kept the city in subjection until 1814. Since then it has shared in most of the revolutionary movements that have swept over Spain, and has frequently been distinguished by the violence of its civic commotions. For the historic antagonism between the Catalans and the other inhabitants of Spain was strengthened by the industrial development of Barcelona. Among the enterprising and shrewd Catalans, who look upon their rulers as reactionary, and reserve all their sympathies for the Provençal neighbours whom they so nearly resemble in race, language and temperament, French influence and republican ideals spread rapidly; taking the form partly of powerful labour and socialist organizations, partly of less reputable bodies, revolutionary and even anarchist.

Strikes are very common, seventy-three having occurred in such a year of comparative quiet as 1903; but the causes of disturbance are almost as often political as economic, and the annals of the city include a long list of revolutionary riots and bomb outrages. A strange contrast is presented by the co-existence of these turbulent elements with the more old-fashioned Spanish society of Barcelona. Church festivals, civic and ecclesiastical processions are almost as animated and picturesque as in Seville itself; and many medieval customs continue to flourish side by side with the most modern features of industrial life, giving to Barcelona a character altogether unique among Spanish cities.

The literature relating to Barcelona is extensive. For a general description of the city, see A. A. P. Arimon, Barcelona antigua y moderna, two illustrated folio volumes (Madrid, 1850); and J. Artigas y Feiner, Guia itineraria de Barcelona (Barcelona, 1888). For the antiquities, see S. Sampere, Topografia antigua de Barcelona (1890). The economic history of the city is dealt with by A. Capmany in his Memorias historicas sobra la marina, comercio, y artes de la antigua ciudad de Barcelona (Madrid, 1779-1792); and, for its political history, the same work should be consulted, together with Historias e conquestas dels comtes de Barcelona, by T. Tomich (Barcelona, 1888), and the Colecció de documents inédits del Arxin municipal de la ciutat de Barcelona (Barcelona, 1892). The spread of the revolutionary movement is traced by M. Gil Maestre, in his El Anarquismo en España, y el especial de Barcelona (Madrid, 1897), and in his La Criminalidad en Barcelona (Barcelona, 1886).