Hosius of Corduba was a prominent 4th-century bishop from Hispania who served as a key advisor to Emperor Constantine the Great. As a leading figure during the Arian controversy, he was a staunch defender of homoousion Christianity. He participated in several significant ecclesiastical gatherings, most notably presiding over the First Council of Nicaea. Throughout his long career, he maintained significant influence within the Roman Empire, eventually facing exile in Sirmium due to his refusal to yield to imperial pressure regarding church doctrine.