The origin of the mollusk collections under the care of the Smithsonian Institution predates the formal establishment of the Department of Mollusks in 1880. Collections of shells began arriving at the Institution from many of the early exploring expeditions conducted during the 1840s and 1850s. Voluntary assistance in arranging and describing the collections was provided by many eminent invertebrate zoologists including Augustus Addison Gould, Philip Pearsall Carpenter, Isaac Lea, William Greene Binney, William Stimpson, and Thomas Bland.
The Department of Mollusks was created as an administrative unit of the United States National Museum (USNM) in 1880. As a result of an administrative reorganization of the USNM in 1897, the name was changed to the Division of Mollusks. In 1914, the Division was merged with the Division of Marine Invertebrates under the latter title. In 1921, the Division of Mollusks regained independent status. At that time the coral and helminthological collections were turned over to the Division's care.
William H. Dall's association with the Smithsonian began in 1865 when he came under the influence of Spencer F. Baird while preparing for his role on the Western Union Telegraph Expedition. After he returned from Alaska in 1868, Dall was given space in the Smithsonian Building to arrange his collections and prepare his scientific reports. While Dall spent the majority of his career as a paleontologist with the United States Geological Survey, he also served as Honorary Curator of the Division of Mollusks from 1880 until his death in 1927. Dall was the author of over 1,600 scientific papers on both recent and fossil mollusks.
Paul Bartsch, an authority on West Indian land shells, was appointed Aid in 1896. He served as Assistant Curator, 1906-1916, and Curator, 1916-1946. After his retirement he was an Associate in Zoology until his death in 1960. Harald A. Rehder joined the staff in 1932 as Senior Scientific Aid. He was promoted to Assistant Curator, 1934-1942; Associate Curator, 1942-1946; Curator, 1946-1965; and Senior Zoologist, 1965-1980. Rehder specialized in the study of the marine mollusks of the Indo-Pacific region. He maintained the title of Zoologist Emeritus until his death in 1996.
Other staff members of the Division of Mollusks have included Robert Edwards Carter Stearns, Assistant Curator, 1884-1893, and Associate in Zoology, 1894-1909; Charles Torrey Simpson, Aid, 1889-1902; William B. Marshall, Aid, 1895-1896, 1903-1914, and Assistant Curator, 1914-1934; Horace G. Richards, Assistant Curator, 1932; Joseph P. E. Morrison, Senior Scientific Aid, 1934-1942, Assistant Curator, 1942-1946, and Associate Curator, 1946-1974; R. Tucker Abbott, Assistant Curator, 1946-1949, and Associate Curator, 1949-1954; Joseph Rosewater, Associate Curator, 1961-1969, and Curator, 1969-1985; Clyde F. E. Roper, Associate Curator, 1966-1972, and Curator, 1972 - ; Richard S. Houbrick, Associate Curator, 1977-1978, and Curator, 1978 - ; and Arthur H. Clarke, Associate Curator, 1977-1980.