In 1861, with the outbreak of the American Civil War, voters in Austin, Bastrop, and other Central Texas communities and counties voted against secession. However, as the war progressed and fears of attack by Union forces increased, the communities contributed hundreds of men to the Confederate forces. With the end of the war and the emancipation of Texas slaves, the African American population of the area swelled dramatically. Black communities such as Wheatville, Pleasant Hill, and Clarksville were established around Austin by these newcomers. The postwar period saw dramatic population and economic growth. The town of Bastrop became a significant manufacturing center producing iron, coal, and textiles. The Chisolm Trail, one of the major routes for exporting cattle, passed through the region. The opening of the Houston and Texas Central Railway, connecting Austin with Houston, transformed Austin into the major trading center for the region. However, as new railroads were built through the region in the 1870s, Round Rock and other communities took over much of Austin's role as a trading center. In 1868 the Coronal Institute was established in San Marcos and in 1873 Texas University (later renamed Southwestern University) was opened in Georgetown following the consolidation of five earlier colleges. During the 1880s Austin gained new prominence as the state capitol building was constructed and other universities were established in the area, most notably the University of Texas. Cattle and cotton production were major economic drivers for many outlying communities. In the late 19th century Austin expanded its city limits to more than three times its former area and the Austin Dam was built to power a new street car line and the new municipal water system.