The rapidly evolving morphology of nineteenth-century New York mirrored the restless energy of the city's elites, which were constantly replenished with new members from diverse socioeconomic backgrounds, in the risk-taking environment of competitive capitalism. As merchant and business interests made room for investment and commercial banking, insurance and financial speculations, railroad corporations, and industrial innovations, the premiere financial district developed along Wall Street. New York's financial interests took a lead in developing the nationwide railroad system in the late nineteenth century. In addition to bringing vast profits to local entrepreneurs like the Vanderbilts, expansion of the national railroads firmly established the hegemony of New York City in an integrated national economy. Wharves and warehouses gradually relocated from the East River to the west side of Manhattan along the Hudson River, where in 1850 Cornelius Vanderbilt built a railroad, a depot, and a warehouse. On the facade of the warehouse was a huge bas-relief statue of himself, overlooking the railroad and the steamships. The most prominent buildings in New York City already were monuments to business, industry, transportation, and government.Transformation of the mercantile city by industrialization led to unprecedented size, functional complexity, and social-class segregation. The population of New York City, which then included only present-day Manhattan and the Bronx, rose sharply from about 125,000 in 1820 to 1.4 million in 1890. Concurrently, the population of nearby Brooklyn, a separate municipality until 1898, soared from 7,000 to 838,000.