south, became the second-to-last annexation, which occurred in 1926. African American migrants started arriving during World War I during the Great Migration. Another wave arrived during and after World War II. They found crowded living conditions and limited employment opportunities, but also higher wages and better schools and social services. Local organizations such as the Albany Inter-Racial Council and churches, helped them, but de facto segregation and discrimination remained well into the late 20th century. Corning administration (1942) to present day Erastus Corning 2nd, arguably Albany's most notable mayor (and great-grandson of the former mayor of the same name), was elected in 1941. Although he was the longest-serving mayor of any city in United States history (1942 until his death in 1983), one historian describes Corning's tenure as "long on years, short on accomplishments." Grondahl said that Corning preferred to maintain the status quo, which held back potential progress during his tenure. While Corning brought stability to the office of mayor, even his admirers cannot come up with a sizable list of "major concrete Corning achievements." Because there was limited new development in this period, much of Albany's historic architecture survived and has been newly appreciated since the late 20th century. During the 1950s and 1960s, a time when federal aid for urban renewal was plentiful, Albany did not see much progress in either commerce or infrastructure. It lost more than 20 percent of its population during the Corning years, and most of the downtown businesses moved to the suburbs, following residents who had gone to newer housing. While many cities across the country struggled with similar issues, the problems were magnified in Albany: interference from the Democratic political machine hindered progress considerably. Governor Nelson Rockefeller (1959–1973) (R) wanted to improve the capital and state university and envisioned a monumental city; he was the driving force behind the construction of the Empire State Plaza, SUNY Albany's uptown campus, and much of the W. Averell Harriman State Office Building Campus. Albany County Republican Chairman Joseph C. Frangella once quipped, "Governor Rockefeller was the best mayor Albany ever had." Though opposed to the project, Mayor Corning negotiated the payment plan for the Empire State Plaza. Rockefeller did not want to be limited by the Legislature's power of the purse, so Corning devised a plan to have the county pay for the construction and have the state sign a lease-ownership agreement. The state