Russia’s brutal invasion in February 2022 revitalized considerations about how Ukraine can contribute to historiographical issues related to the origins of nation-statehood. This essay contributes to that discussion by returning to the 19th century and exploring how the participants in multiple archeological congresses, nascent social scientists confident in the empirical objectivity of their evidence, envisioned Ukraine. Borrowing from Benedict Anderson’s commonplace about a nation as an “imagined community,” I highlight the contestation between nationalist and imperialist discourses in the emergent social sciences. Although the Versailles Peace Conference, which denied Ukraine the opportunity to “self-determine” as a modern political entity, revealed the limits of the Western political imagination in 1919, many of the ideas presented at these congresses continue to inform the cultural and geographical borders of Ukraine.

Soon to celebrate his centennial year, Michael Loewe is certainly the most eminent Han historian today. Without his numerous publications—including not only such foundational reference works as The Biographical Dictionary of Qin and Western Han and Early Chinese Texts but also a wide range of more specialized studies—it is hard to imagine how the once-neglected field of Han history could have garnered such respect among scholars in allied fields in Euro-America and abroad. In these introductory remarks, we reflect on Michael Loewe's distinguished contributions to the field of early Chinese history over several decades and his extraordinary record as teacher. We draw special attention to several ways in which Professor Loewe's work continues to challenge such outdated and anachronistic paradigms as “Confucianism,” and we note the careful ways he correlates received, “found,” and excavated sources. We conclude the introduction with a set of reflections situating Professor Loewe as teacher within a distinguished Sinological lineage.

Ancient Roman concrete presents exceptional durability, low-carbon footprint, and interlocking minerals that add cohesion to the final composition. Understanding of the structural characteristics of these materials using X-ray tomography (XRT) is of paramount importance in the process of designing future materials with similar complex heterogeneous structures. We introduce Materials Data Science algorithms centered on image analysis of XRT that support inspection and quantification of microstructure from ancient Roman concrete samples. By using XRT imaging, we access properties of two concrete samples in terms of three different material phases as well as estimation of materials fraction, visualization of the porous network and density gradients. These samples present remarkable durability in comparison with the concrete using Portland cement and nonreactive aggregates. Internal structures and respective organization might be the key to construction durability as these samples come from ocean-submersed archeological findings dated from about two thousand years ago. These are preliminary results that highlight the advantages of using non-destructive 3D XRT combined with computer vision and machine learning methods for systematic characterization of complex and irreproducible materials such as archeological samples. One significant impact of this work is the ability to reduce the amount of data for several computations to be held at minimalistic computational infrastructure, near real-time, and potentially during beamtime while materials scientists are still at the imaging facilities.

We divide the corrosion products on ancient bronzes into two categories, i.e., "inward growth" and “outward growth” corrosions. Several selected Chinese ancient bronzes with the "inward growth” corrosion are studied; and their chemical compositions, microstructures and morphologies are characterized systematically. According to the results, it is found that the “inward growth” corrosion can be further divided into three types, i.e., "noble patina", "noble-like patina" and "lamellar peeling patina". We propose that the growth mechanism of the “inward growth” corrosion is that the corrosion initiates at and develops along α-Cu phase. Furthermore, the effect of alloy Sn content on the “inward growth” corrosion is also studied.

Recent advancements in accelerator mass spectroscopic (AMS) radiocarbon (14C) analytical methods and instrumentation offer us reliable conventional 14C ages with highly reduced analytical uncertainty for archeological bone collagen. However, after calibration this may be still too high for archeologists in periods where archeochronology is capable of attaining a resolution of 25–30 yr. Furthermore, there are cases when wiggles in the calibration curve yield wider age ranges than initially expected. For the Avar Age in the Carpathian Basin (568 to early 9th century AD) reliable archeotypochronology is available for the 7th century AD alone. The date of Avar invasion (568 AD) is precisely known. Precise archeological dating for the late 6th and the 9th centuries is lacking, calling for other methods to be introduced. This paper reports the first 14C dates for an Early Avar Age cemetery, Makó-Mikócsa. According to archeotypochronology, the cemetery was in use for three generations until the mid-7th century AD. The imprecision in 14C chronology arising from wiggles in the IntCal13 curve was significantly reduced by relative stratigraphy-controlled Bayesian modeling. Introduction of further age constraints from archeotypochronology into the model reduces broad absolute age ranges providing more constraint ages.

Scholars attribute the growth and decline of Classic period (AD 200–900) settlements in the semi-arid northern frontier zone of Mesoamerica to rainfall cycles that controlled the extent of arable land. However, there is little empirical evidence to support this claim. We present phytolith, organic carbon, and magnetic susceptibility analyses of a 4000-yr alluvial record of climate and human land use from the Malpaso Valley, the site of one such Classic frontier community. The earliest farming occupation is detected around 500 BC and appears related to a slight increase of aridity, similar to the level of the modern day valley. By AD 500, the valley's Classic period Mesoamerican settlements were founded under these same dry conditions, which continued into the Postclassic period. This indicates that the La Quemada occupation did not develop during a period of increased rainfall, but rather an arid phase. The most dramatic changes detected in the valley resulted from the erosion associated with Spanish Colonial grazing and deforestation that began in the 16th century. The landscape of the modern Malpaso Valley is thus primarily the product of a series of intense and rapid transformations that were concentrated within the last 400 yr.

In northeastern Kuwait, ancient beach ridges and associated berms are separated from the present shoreline by a 4–6 km-wide sabkha. A diverse mollusk fauna in the beach ridges attests to a former open marine environment. A total of 21 AMS dates were obtained in this study. Thirteen mollusk samples from beach ridges yielded AMS dates ranging from ~ 6990 cal yr BP in the southeast to ~ 3370 cal yr BP in the northwest, suggesting a southeast to northwest age progression during the Holocene transgression. In contrast, four samples from berms throughout the study area yielded AMS dates of 5195–3350 cal yr BP showing no age progression; these berms consist largely of Conomurex persicus gastropods that aggregated by storms during a highstand at ~ 5000–3500 cal yr BP. The berms are presently at ~ + 6 m above sea level, 2–3 m above the beach ridges. Human settlements were common on the ridge crests before and after the highstand. Regression to present-day sea level commenced after the highstand, which is when the sabkha began forming. A landward, marine-built terrace, which yielded AMS dates > 43,500 14C yr BP, probably formed during Marine Oxygen Isotope Stage 5e and hence is not genetically related to the beach ridges.