Historical Context
Euschemon's episcopate fell within the iconoclast controversy that divided the Byzantine Church and empire over the veneration of religious images. The reign of Theophilus (829-842) marked the last active phase of imperial iconoclasm; the dispute was settled after his death with the restoration of the icons in 843, commemorated as the Triumph of Orthodoxy. Bishops and monastics who upheld the icons through this period and endured imprisonment or exile, as Euschemon did, were honored with the title of Confessor.
By tradition Euschemon is identified as a correspondent of Saint Theodore the Studite, the prominent monastic leader and defender of the icons, which would place him within the wider network of iconophile clergy of the era. This connection is reported in reference literature rather than in the brief synaxarion notices, and should be received as traditional attribution.