The site of Philadelphia was first organized into a town under the Swedes in the 1640s and, after considerable fighting, was finally taken by the English in 1674. It became a prime destination for Quaker and German immigrants seeking to take advantage of Penn’s guarantees of religious liberty and bountiful land. Most of these settlers moved into the countryside in the southeastern corner of the colony. Philadelphia itself provided many economic opportunities, however. There were many Quaker merchants and businessmen who took advantage of the fine natural harbor at the confluence of the Delaware and Schuylkill Rivers. By 1710, it had become the largest city in the thirteen colonies—with a population of about 35,000 on the eve of the American Revolution (1775–83)—and remained so until the 1780s, when it was overtaken by New York City (see New York, New York). Philadelphia was at the center of the Revolution, hosting the First and Second Continental Congresses (1774–75), being occupied by the British (1777–78), and serving as the meeting place for Congress for the remainder of the war (1778–83). The Constitutional Convention was also held in Philadelphia (1787).
The rapid development of canals, railroads, and other industrial projects attracted large numbers of immigrants during the 19th century, though Philadelphia was no longer a major port of disembarkation. Irish and German immigrants predominated before the Civil War (1861–65), finding many opportunities in Philadelphia’s rapidly expanding economy. By the 1840s, the Irish constituted 10 percent of the population. As in most northeastern cities, nativism was strong, with considerable prejudice displayed toward the Irish in particular, who often were willing to work for considerably lower wages than their American-born counterparts. This sparked an ongoing series of anti-Irish riots between May and July of 1844.
Like most eastern seaboard cities, Philadelphia attracted thousands of Jews, Italians, Poles, and Slavs after 1880. As the port of New York became busier with the massive influx of the new immigration, Philadelphia processed an increasing number of immigrants at its Washington Avenue immigration station, located on the Delaware River in the heart of the wharf district. In 1909, Congress appropriated funds for a new station. Ultimately, the project was abandoned as World War I (1914–18) and restrictive immigration legislation between 1917 and 1924 effectively stemmed the immigrant tide. The city’s population grew rapidly, from 850,000 in 1880 to 1.8 million in 1920. The major source of increase after World War II (1939–45), however, was African Americans moving from the south in search of economic opportunities. By 1970, more than one-third of Philadelphia proper was black. After 1965, Philadelphia declined dramatically as a preferred location for immigrant settlement. As European immigration declined and Hispanic (see Hispanic and related terms) and Asian immigration increased, Los Angeles, San Diego, and San Francisco in California; Miami, Florida; Houston, Texas; and Washington, D.C., all overtook Philadelphia. Among large metropolitan areas in 2000, Philadelphia had the lowest percentage of foreignborn population at 5.1 percent.