Membership in the American Institute of Architects was originally divided into two categories, Professional and Associate, with the former largely corresponding to the later title of Fellow. This title was first proposed in 1864 by Calvert Vaux, and by at least 1867 was in common use. Earlier Professional members, including several of the founders, began using the title at this time, and prior Professional members are now considered Fellows. During this period, the title was considered a senior rather than honorary title. In 1889, the AIA was merged with the Western Association of Architects (WAA), which had designated all of its members Fellows. Upon the merger, WAA members kept their title and all existing AIA members were raised to Fellowship. Beginning in 1890, Fellowship was the primary form of membership in the AIA, in addition to "Honorary and Corresponding" members, who, as in the present, were non-architects or foreign nationals.College of Fellows History & Directory, 2017 ed. (Washington: American Institute of Architects, 2017)
