The two persons most responsible for the founding of the IMS in 1935 were Henry Rietz and Harry Carver, and some background about each of them is given. Others who had some important roles to play were Cecil Craig, Allen Craig, Sam Wilks, Al O'Toole, Walter Shewhart, Paul Rider, and Harold Hotelling. Fred Stephan, then the executive secretary of the American Statistical Association, wanted IMS to be one of ASA's sections and worked very hard to smooth the way for that type of relationship. While Rietz also leaned in that direction, Carver did not trust ASA at that time and wanted nothing to do with that arrangement. In 1938, three years after IMS was established, Carver officially turned his Annals of Mathematical Statistics over to IMS; and IMS's initial editorial board consisted of Sam Wilks, Jerzy Neyman, and Allen Craig.
"On the Origins of the Institute of Mathematical Statistics." Statist. Sci. 1 (2) 285 - 291, May, 1986. https://doi.org/10.1214/ss/1177013709