Instrumental neutron activation analysis (INAA) was employed on 201 ceramic and clay samples from the Igbomina region of northern Yoruba in Nigeria. Ceramic data were obtained from 13 settlement sites spread over four Igbomina localities whose dates range between A.D. 1400 and A.D. 1800, and five raw clay samples from riverbeds and modern potters located in the Igbomina culture area. Quantitative analysis of the INAA data resulted in identification of four ceramic compositional groups that can be attributed to specific locales within the region. These results indicate that ceramics were moved within and among various Igbomina geographic areas and villages as well Ilorin (a Yoruba center located northeast of Igbomina). Results generated from this analysis indicate the tremendous potential for examining regional interaction in Yorubaland immediately before and during the Old Oyo period (fifteenth to the eighteenth century A.D.), a time of sociopolitical and settlement change.