<p> Archaeological excavations by the Proyecto Arqueol&oacute;gico-Paleoetnobot&aacute;nico R&iacute;o Jama (PAPRJ) in the Jama River Valley of northern Manab&iacute;, Ecuador, have established a cultural chronology spanning over three millennia of prehispanic occupation. One of these occupations, the Tabuchila Complex of the Late Formative Period (1000 &ndash; 500 BCE), remains poorly understood. Excavations at three sites in the Jama Valley in the 1990s recovered ceramic, lithic, obsidian, paleobotanical, archaeofaunal, and human skeletal remains from Late Formative Tabuchila contexts, with the goal of orienting Late Formative occupation of the northern Manab&iacute; region to its contemporaries in western lowland Ecuador. </p><p> This study employs modal ceramic analysis to recognize and catalogue formal and stylistic variation within the recovered Tabuchila ceramic assemblage. Through this analysis the Tabuchila assemblage is compared to other studies of Late Formative Chorrera assemblages to understand how Tabuchila represented a regional variant of and contributor to the formation of the Chorrera ceramic tradition. In addition, a sovereignty-based theoretical approach explores how this ceramic assemblage reflects deeper processes of emergent social complexity and early attempts at establishing inequality in northern Manab&iacute;&rsquo;s regional mound center of San Isidro. Results and discussions of the analysis examine a community connected with its Middle and Late Formative contemporaries across the western lowlands and engaged in feasting activity in the vicinity of the central mound of San Isidro.</p>