In April 1989, after successful presentations on 18th century México and Spain during the Annual Meeting of ASECS in New Orleans, Theodore E. D. Braun, at the time ASECS Coordinator of Affiliate Societies, proposed that a new affiliate on Ibero-American 18th century studies be established. He agreed to serve as chair of the organizing committee for such an society, and proceeded to appoint the following persons to serve on that committee: Clara Bargellini (México), María Agueda Méndez (México), Graciela Palau de Nemes (USA), Eva Rudat Kahiluoto (USA), María Salgado (USA), and Pilar Sáenz (USA).
Subsequently, he appointed the following committee to draft a constitution: Clara Bargellini, María Agueda Méndez, María Salgado, Pilar Sáenz, and William Bryant (coordinator).
In August, María Salgado and Pilar Sáenz completed the final draft of the new constitution while at a congress of the Asociación Internacional de Hispanistas in Barcelona. In September 1989 the draft was submitted to T.E.D. Braun for approval. In November 1989 Braun, as Coordinator of Affiliate Societies, proposed to the ASECS Executive Board affiliate status for the Ibero-American Society for Eighteenth-Century Studies.
Having received approval from ASECS for the new IASECS as an affiliate society, the charter meeting, chaired by T.E.D. Braun, took place on 16 April 1990 during the Annual Meeting of ASECS in Minneapolis. There the constitution was adopted and officers were elected.
Thus IASECS was officially launched.