The Philadelphia Convention Hall and Civic Center, more commonly known as the Philadelphia Civic Center and the Philadelphia Convention Center, was a complex of five or more buildings evolved out of a series of buildings dedicated to expanding trade which began with the National Export Exhibition in 1899. There were two important buildings on the site. The Commercial Museum, built in 1899, was one of the original exposition buildings. The Municipal Auditorium (Convention Hall), built in 1931, Philip H. Johnson, architect. The site was host to national political conventions in 1900, 1936, 1940 and 1948.