May 22, 337: Constantine, the first Christian emperor of Rome, dies. Though known for calling the Council of Nicaea (which condemned the Arian heresy) and for beginning the process of Christianizing the empire, he waited until just before his death before he finally accepted baptism into the church (see issue 57: Converting the Empire).
May 22, 452: Leo, bishop of Rome, sends three angry letters to protest the Council of Chalcedon's recent elevation of Constantinople to the preeminent see in Christendom. The two cities had been placed on equal footing by a 381 ecumenical council in Constantinople, but Chalcedon tipped the scale, saying that since the imperial capital had moved to "New Rome" (Constantinople), that city deserved the benefits Rome once enjoyed. This event was one of many leading up to the East-West schism of 1054 (see issue 54: Eastern Orthodoxy).
May 22, 1883: Billy SunDay , who would become the greatest American tent revivalist after a career in professional baseball, has his first at bat playing for the Chicago White Stockings. He struck out his first 14 attempts.