Severinus was a Roman bishop elected as pope in October 638. His brief leadership was defined by a significant theological conflict with the Byzantine Emperor Heraclius. Because he refused to endorse Monothelitism, the imperial government withheld formal recognition of his election for over eighteen months. This political standoff involved attempts to plunder the Lateran Palace and pressure the new pontiff through local officials. Although his authority was eventually sanctioned in May 640, he passed away only two months later in August of that same year.