Josaphat Kuncewitcz was born about the year 1580 at Vladimir, Volhynia, [part of the Polish province of Lithuania at the time] and given the name John at baptism. While being instructed as a child on the sufferings of our Savior, his heart is said to have been wounded by an arrow from the sacred side of the Crucified. In 1604 he joined the Ukrainian Order of Saint Basil (Basilians), lived as a monk in a very mortified life, went barefoot even in winter, refrained from the use of wine and flesh-meat, and always wore a penitential garb. In 1614 he was appointed archimandrite of Vilna, Russia and four years later archbishop of Polotzk; in this position he worked untiringly for Church reunion. He was a great friend of the poor, once even pledged his archepiscopal omophorion (pallium) to support a poor widow. The foes of union decided to αssαssιnαtҽ him. In a sermon, he himself spoke of his death as imminent. When he visited Vitebsk (now in Russia), his enemies attacked his lodging and murdered a number of his companions. Meekly the man of God hastened toward the mob and, full of love, cried, "My children, what are you doing? If you have something against me, see, here I am." With furious cries of "Kill the papist!", they rushed upon him with gun and sword. Josaphat's body was thrown into the river but emerged, surrounded by rays of light, and was recovered. His murderers, when sentenced to death, repented their crime and became Catholics.

http://www.catholicculture.org/culture/liturgicalyear/calendar/day.cfm?date=2014-11-12