Joachim the Korsunian was an early Eastern Orthodox bishop who served as the first prelate of Novgorod from approximately 989 until 1030. Originating from the Byzantine town of Cherson, he likely traveled to Kievan Rus' during the period of Christianization. His leadership was instrumental in establishing the new faith in the region, where he replaced pagan sites with Christian structures, including the first wooden Cathedral of Holy Wisdom.