From the LCMS website:
Boniface was born in the late seventh century in England. Though he was educated, became a monk, and was ordained as a presbyter in England, he was inspired by the example of others to become a missionary. Upon receiving a papal commission in 719 to work in Germany, Boniface devoted himself to planting, organizing, and reforming churches and monasteries in Hesse, Thuringia, and Bavaria. After becoming an archbishop, Boniface was assigned to the See of Mainz in 743. Ten years later he resigned his position to engage in mission work in the Netherlands. On June 5, 754, while awaiting a group of converts for confirmation, Boniface and his companions were murdered by a band of pagans. Boniface is known as the apostle and missionary to the Germans.