The Northern Dynasties period (AD 386-581) in China witnessed significant interactions between Han (agricultural) and non-Han (pastoral/nomadic) populations, leading to debates about the extent of “hybridization” – a process of cultural and ethnic blending. While historical accounts offer insights, archaeological evidence has been limited. This study addresses this gap by analyzing stable isotope ratios (δ¹³C and δ¹⁵N) in human bone collagen from both elite and commoner burials in the Chang’an region during the sixth century AD. The shift of the Northern Wei capital to the Central Plains (AD 493) provides a crucial backdrop for understanding dietary changes. By analyzing the isotopic signatures, the researchers aim to quantitatively reconstruct the dietary profiles of different social groups, shedding light on the complex interplay between ethnicity, foodways, and social status during this period of intense cultural exchange in the heartland of medieval Imperial China, during the reign of the Northern Zhou. The focus is the capital city of Chang'an, whose dietary and social dynamics would significantly impact the Sui and Tang Dynasties that would follow.

Existing scholarship on the Northern Dynasties focuses on the interactions between Han and non-Han populations, with debates centering on the relative dominance of “Han-ization” (cultural assimilation of non-Han elites into Han culture) versus “Xianbei-ization” (the promotion of Xianbei culture amongst elites and its adoption by Han people). While previous research points to some degree of cultural integration, quantitative archaeological studies examining dietary patterns to illuminate the nature of this integration have been lacking. This study addresses this gap using scientific methods to contribute new data about foodways to the ongoing discussions of hybridity in the Northern Dynasties.

The study analyzed stable carbon and nitrogen isotope ratios (δ¹³C and δ¹⁵N) in collagen extracted from human bone samples (n=23) from eight noble and nine commoner burials in the Guanzhong Basin, around Chang'an. Samples included remains of Emperor Wu and Empress A'shina of the Northern Zhou Dynasty and other nobles, spanning roughly a century (AD 503-604). Collagen extraction followed established protocols, with isotopic measurements performed using an IsoPrime 100 IRMS coupled with an Elementar Vario. Additionally, three domesticated animal samples from the tomb of Emperor Wu were analyzed. To provide a broader geographical and dietary context, the researchers compiled a secondary dataset of human stable isotopic data (n=1233) from across northern China and neighboring regions, spanning from 550 BC to AD 1200. The δ¹³C values were used to assess the proportion of C3 (wheat, barley) and C4 (millet) plants in the diet, while δ¹⁵N values provided insights into protein intake (meat and milk). Isotope values from different bone types (long bones for long-term diet, ribs/vertebrae for late-life diet) were analyzed to assess dietary changes throughout individuals' lives. The researchers utilized thresholds of -18‰ and -12‰ for δ¹³C to differentiate between predominantly C3, mixed C3/C4, and fully C4 diets. The data were then compared and contrasted between the elite and commoner groups, with this data analyzed in relation to the existing database of human stable isotope data for the study area during the specified timeframe.

The isotopic analysis revealed significant differences in dietary patterns between elite and commoner groups. Elites exhibited higher δ¹⁵N values, indicating greater protein consumption (meat and milk products) and better overall nutrition compared to commoners. However, even within the elite group, there was variation in δ¹³C and δ¹⁵N values, reflecting diverse dietary practices. Xianbei nobles showed a spectrum of diets ranging from primarily pastoral (high δ¹⁵N and low δ¹³C) to increasingly agricultural (higher δ¹³C, lower δ¹⁵N) depending on their level of integration in the agrarian economy and political status. The most prominent Xianbei elite exhibited dietary shifts over their lifetimes, in some cases shifting towards more C4 plant consumption in their later lives. Lower-ranking nobles show a closer dietary pattern to Han nobles and commoners, suggesting a greater level of integration into the Han agricultural lifestyle. Commoners exhibited a mixed C3/C4 diet, with considerable variation in δ¹³C likely due to varying levels of access to different food types and varied agricultural practices. Comparison with the larger dataset shows the Xianbei elite dietary habits generally aligned with nomadic groups from the Mongolian Plateau, while commoners showed dietary convergence with agricultural populations from the North China Plain. The study identified a 3.3‰ difference in mean δ¹⁵N values between nobles and commoners, demonstrating a nutritional gap between social classes. The study also revealed dietary distinctions between individuals even within the same families, suggesting differences in status and access to resources, with some showing more assimilation toward an agricultural diet in their later years.

The findings challenge simplistic notions of “Han-ization” or “Xianbei-ization,” revealing a more complex interaction between Han and Xianbei identities and dietary practices. The results suggest a two-way process of cultural exchange at both elite and commoner levels. Elite Xianbei migrants gradually incorporated agricultural elements into their diet. The degree of assimilation varied depending on social status and the length of residency in Chang'an. Commoners, however, show a higher degree of dietary heterogeneity, reflecting the broader economic and social transformations that were occurring. The results demonstrate how dietary data can illuminate the complex process of cultural integration and identity formation in a multi-ethnic society. The degree of integration into the agricultural food system, therefore, may have reflected an elite strategy of assimilation and power consolidation. These findings showcase the nuanced patterns of cultural exchange and economic integration in medieval northern China. Furthermore, this study suggests that the integration of different cultures, foodways and lifestyles under a single political regime was a significant catalyst for the cultural and economic prosperity of the succeeding Sui and Tang Dynasties.

This study contributes significantly to the understanding of social dynamics and cultural exchange in medieval China by utilizing stable isotope analysis to illuminate the complex interplay of agricultural and pastoral foodways in Chang’an. The findings demonstrate the nuanced and multifaceted nature of cultural interactions, challenging previous interpretations of either dominant Sinicization or Xianbei-ization. Further research with expanded commoner samples and analyses of a wider range of crops and animals could provide even more detailed insights into the dietary practices and cultural integration processes during this pivotal period in Chinese history. The findings presented here provide a solid foundation for expanding the investigation of foodways as a key indicator of social and cultural change.

The study's limitations include the relatively small sample size for commoners and the reliance on existing datasets for comparison. While the methodology is robust, the interpretation of isotopic data relies on assumptions about the relationship between diet, isotopic signatures, and cultural practices, which are inherently complex. Future research could benefit from a larger sample size of commoner remains, especially for the Sui-Tang period, alongside more detailed analyses of the plant and animal remains found in the burials to further refine the understanding of food production and consumption practices.