This study investigates the presence of Nestorianism in Manchuria and the Korean Peninsula during the Silla and Parhae periods (eighth–tenth centuries), with a focus on archaeological evidence such as the stone cross from Pulguksa Temple and the clay crucifix from the Abrikos site in Parhae. These findings suggest that Nestorianism often merged discreetly with local belief systems rather than asserting itself overtly. The stone crosses at Pulguksa, for example, likely reflect the covert practices of Nestorian adherents, aligning with their historical tendency to integrate subtly into existing cultural and religious frameworks. The research highlights several key contributions. First, it challenges theological perspectives that overemphasize Nestorian traces in Korea as precursors to modern Christianity, arguing instead for a nuanced understanding rooted in the cultural exchanges of the Silk Road. A rigorous archaeological approach is necessary to substantiate the presence and significance of Nestorianism in the region, moving beyond fragmented interpretations of artifacts. Second, the study emphasizes the need to analyze Nestorianism’s unique characteristics through its material culture. Most known Nestorian artifacts are concentrated in Mongolia and Inner Mongolia during the Yuan dynasty, with earlier evidence largely consisting of tombstones with engraved crosses. This pattern is consistent with other persecuted religious groups, where material traces are limited due to suppression. Nestorianism’s integration into East Asian cultures involved adopting elements of Buddhism and Confucianism, demonstrating remarkable flexibility and indigenization. This suggests a different archaeological approach is required to identify Nestorian traces compared to other religions. Finally, while Nestorian-related materials in Korea and Japan are fragmentary, they are steadily emerging. The introduction of Nestorianism to these regions was likely facilitated by small groups of Sogdian merchants and artisans, rather than through large-scale missionary efforts. In Korea, the stone cross at Pulguksa Temple is believed to have been discreetly integrated into Buddhist architecture, reflecting the subtle yet significant impact of Nestorianism on local culture. In conclusion, Nestorianism left behind subtle traces in the cultural exchanges along the Silk Road and East Asia. The growing body of archaeological evidence provides a foundation for exploring Nestorianism’s contributions to East-West civilizational exchange and medieval Korean culture, moving beyond preconceived notions and highlighting the interconnectedness of East Asian cultures during the Silla and Parhae periods.