This paper introduces the articles that comprise this Special Issue on Izapa. First, we review early reporting and assessments of Izapa's monuments as well as archaeological investigations undertaken at the site during the twentieth century. Next, we describe more recent developments in interpretation and new archeological excavations and survey data collected during the past two decades. The papers in this Special Issue present new information that contribute to our evolving understanding of Izapa during the millennium that stretches from the Middle Formative period through the Middle Classic period (700 b.c.–a.d. 600). They serve as a status report on our understanding of the still largely enigmatic ancient kingdom, its regional structure, and connections to contemporaneous Isthmian sites.

Two burials excavated at Izapa in 1963 have special green obsidian artifacts made at Teotihuacan. We describe the contexts and contents of these burials and consider the significance of their contents in light of Spence's (1996) model of Teotihuacan exchange of obsidian objects. We interpret the Izapa artifacts as gifted objects indicative of the political independence of Izapa in Middle Classic times.

Extensive investigation at the archaeological site of Izapa in southern Chiapas, Mexico, by the New World Archaeological Foundation yielded few burials at the site's core ceremonial precinct. Those found were located on the acropolis that supports Mound 30a and defines the north side of Izapa Group B. The majority of caches found in this zone date to the Protoclassic Hato and Itstapa phases (100 b.c.–a.d. 250). The shift in mortuary practices ca. 100 b.c. was accompanied by several changes to the site's occupation and architectural patterns. Study of these mortuary traditions provides important insights regarding the reconfiguration of Izapa's political organization at the turn of the millennium. Comparisons of mortuary practices at Izapa with those of neighboring civic-ceremonial centers El Ujuxte, Takalik Abaj, and Kaminaljuyu during the Preclassic and Protoclassic transitions contextualizes the practices found at Izapa at a regional level.

In southern Mesoamerica, the period between 100 b.c. and a.d. 400 saw both the apogee and fall of several powerful Formative-period cities. Previous reports have suggested that conquest from the southeast may have prompted a unique decline at Izapa around 100 b.c., when many neighboring cities were prospering. Over the last five years, new archaeological data has emerged for the Formative to Classic period transition at Izapa. The present work summarizes these updates and highlights recent deposits excavated during the Izapa Household Archaeology Project. These updates raise questions about the Hato-phase intrusion hypothesis proposed by Lowe and colleagues (1982). I close with an alternative proposal that, beginning around 100 b.c., increased network participation and a change in the institution of kingship produced some of the dramatic changes in ceramics and burial patterns observed at the site.

This paper takes Izapa Stela 21, with its vivid portrayal of captive sacrifice, as the point of departure for an analysis of the ways in which acts of aggression were portrayed in Late Formative monuments from a region that includes the Pacific slope and adjacent highlands of Mexico and Guatemala. It considers the social significance of themes of captive sacrifice and violence, and their role within a larger iconographic system designed to accommodate the mutually reinforcing ideas of ideology and coercive power. While clearly laden with implications of political control, subjugation, deference, and fealty, the imagery also alludes to agricultural fertility, the arrival of rain, and broader notions of social order.

This paper aims to situate the Late Formative urban center of Izapa, Chiapas, Mexico into the greater discussion of early Mesoamerican writing systems. The elites of Izapa produced elaborate carved stone monuments in an era that bore witness to the fluorescence of three great hieroglyphic programs—the Zapotec, the Epi-Olmec, and the Maya—and, yet, only a handful of glyphs appear in Izapa's monumental corpus. In a discussion that includes Izapan iconoglyphs, possible nominal phrases, and the calendrical inscriptions on Izapa Stela 27, Stela 9, and Miscellaneous Monument 60, this study juxtaposes Izapan visual culture with representational systems to the east and west, and ultimately explores the narrative domains of greatest salience to Izapa's elite: image and cyclical time.

Between the years of 30 b.c. to a.d. 80, during the Late Formative period, the site of Izapa was flooded by lahars associated with an explosive eruption of the San Antonio volcano (part of the Tacaná Volcanic Complex). Computer simulations suggest that hot pyroclastic flows did not impact Izapa directly, but did impact the region considerably, filling and clogging the Cahuacan and Mixcun rivers with hot debris. The material was quickly saturated by heavy rains and, as the water from the rivers overtopped the obstruction, remobilized in the form of a hot mixture of mud and water known as a lahar (or flood of volcanic origin), which flowed down through the piedmont zone along the Cahuacan, Mixcun-Suchiate, and Izapa rivers. At Izapa, the flood took the form of a 6-m catastrophic wave of mud and water that likely destroyed crops and caused many causalities, surrounding the architectural mounds at Izapa with a muddy landscape. The floods also dramatically affected the rivers downstream, undoubtedly wreaking serious damage to the transport and trade of goods along the coast.

Izapa is famous for its monumental architecture and extensive corpus of carved stelae dated to the Late Formative Guillén phase (300–100 cal b.c.). The site was first established, however, as the capital of a kingdom during the second half of the Middle Formative period (750–300 cal b.c.). Little is known of the first centuries of the site's occupation or how this early kingdom coalesced with Izapa as its capital. In 2012, the Izapa Regional Settlement Project (IRSP) excavated 21 test units and ran 10 radiocarbon accelerator mass spectrometry (AMS) dates in order to begin correcting this lacuna. These excavations were the first at the site to screen soil matrices and recover artifact samples that can be quantitatively analyzed.

We undertook excavations in areas north and south of Group B, the original center of Izapa. This work dates the northern expansion of the site's main platform (under Mound 30a) to the Terminal Formative Itstapa phase (cal a.d. 100–300) that resulted in a doubling of the platform's size. Further, we documented that there were three distinct construction episodes in the Terminal Formative expansion and that a central staircase and ramp were built of stone during the second episode. Buried below the Terminal Formative platform expansion was a white clay surface built during the Escalón phase (750–500 cal b.c.) and used through to Guillén times. At the long, linear Mound 62 that defines the eastern edge of Izapa's site core, we documented two episodes of Guillén-phase monumental construction. Buried below this construction fill at Mound 62, a hearth feature and stone alignment are dated to the late Middle Formative based on radiocarbon assays and the results of ceramic analysis. Excavations at Mound 72 and 73 documented that Izapa's E-Group (newly recognized with lidar [light detection and ranging] data) was established in the late Middle Formative period and then significantly augmented during the Guillén phase. The architectural program at Izapa saw its apogee during the Late Formative period, but was first established during the preceding centuries of the Middle Formative. Ten new AMS dates confirm the dating of the Escalón, Frontera, and Guillén phases to 750–100 cal b.c.

Ceramic analysis allowed us to differentiate quantitatively between midden deposits and construction fill through the site's occupation and to recognize domestic versus public spaces during the first centuries of the Izapa kingdom's coalescence. We identify late Middle Formative period middens based on the high density of ceramics in addition to good surface preservation of sherds and a lack of temporal mixing of types. The designation of high-artifact density middens contrasts with the contents of Late and Terminal Formative construction fill with lower ceramic sherd densities and mixing of temporally diagnostic types. Off-mound contexts (where construction fill was mined) had even lower ceramic densities than construction fill and the sherds were very eroded. Analysis of ceramic remains from late Middle Formative period midden deposits also allowed us to infer differences in public and domestic areas of the site during the first centuries of its occupation. Formal and metric variables from these ceramic assemblages identify dish-to-jar ratios that differentiate domestic contexts (with an assortment of vessel forms) from more publically oriented areas of the site (with more serving dishes). The differential distribution of rim diameters of fancy and plain dishes allows us to identify areas of Izapa where domestic activities predominate and indicate that more publically oriented feasting practices occurred at the site center near the main pyramid (Mound 30a) during the late Middle Formative period.

Archaeological survey and excavations in the mangrove-estuary zone south of Izapa have generated an understanding of how the environment and human exploitation patterns changed during the Archaic and Formative periods. Archaic-period archaeological remains are not present, but the sedimentary record shows that Archaic people were clearing the coastal-plain forest for agricultural purposes. This activity augmented delivery of sediments to the littoral zone, which expanded the mangrove forest and created a productive environment that could be colonized by Early Formative villagers by around 1600 cal b.c. Population growth during the Early Formative created conditions that favored emergence of specialized pyro-industries, especially salt production, by around 1000 cal b.c. Production intensity increased thereafter, especially during the Late Formative period, coincident with the apogee of Izapa. Salt production became more episodic during the Terminal Formative period, when interior populations were declining to a nadir after cal a.d. 250.

In 1943, Matthew Stirling (1943:72) once opined, “Izapa appears to be much more closely related to the earth-mound sites of southern Veracruz … than it does with sites in the Maya area.” Since then, scholars have postulated ties of varying strength between Late Formative polities on either side of the Isthmus of Tehuantepec. Ceramic similarities have been noted between southern Chiapas and the Gulf Coast, but discussion of Late Formative transisthmian interaction has focused primarily on sculptural similarities between Izapa and sites of the lower Papaloapan basin, including Tres Zapotes, El Mesón, and Alvarado. Indeed, Michael Coe (1965b:773) suggested that the Izapan art style may have originated on the Gulf Coast rather than on the Pacific slope. In this article, we reexamine Late Formative interaction between Izapa and Epi-Olmec polities with an expanded data set based on recent iconographic studies and archaeological investigations in and around Tres Zapotes.