By 500 BCE, San José Mogote's 1000 years of dominance ended, and it was relegated to the status of a lesser community that fell under Monte Albán's control.[7] Dating to the earliest period of occupation at the site, these monuments may depict leaders of competing centers and villages captured by Monte Albán, some identified by name.Inserted within the building walls are over 40 large carved slabs dating to Monte Albán II and depicting place-names, occasionally accompanied by additional writing and in many cases characterized by upside-down heads.Alfonso Caso was the first to identify these stones as "conquest slabs", likely listing places the Monte Albán elites claimed to have conquered and/or controlled.Some of the places listed on Building J slabs have been tentatively identified,[9] and in one case (the Cañada de Cuicatlán region in northern Oaxaca) Zapotec conquest has been confirmed through archaeological survey and excavations.[12] During the Early Classic (period IIIA, 250-450 CE), writing at Monte Albán became largely limited to calendrical sequences, proper names and toponyms, whereas iconography seems to be used for other purposes (Whittaker 1992, p. 6).