Saint Boniface, like most of his delusional ilk, had a profound death-wish which the Heathens of Frisia graciously helped him fulfill. From Butler’s Lives of the Saints:

This apostle of so many nations thought he had yet done nothing, so long as he had not spilt his blood for Christ, and earnestly desired to attain to that happiness. Making use of the privilege which Pope Zachary had granted him of choosing his successor, he consecrated St. Lullus, an Englishman, formerly monk of Malmesbury, archbishop of Mentz, in 754, leaving him to finish the churches which he had begun in Thuringia, and that of Fuld, and conjuring him to apply himself strenuously to the conversion of the remaining idolaters. 

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The saint, looking upon himself as devoted to labour in the conversion of infidels, and being at liberty to follow the call of heaven, would not allow himself any repose, so long as he saw souls perishing in the shades of darkness, and his extreme desire of martyrdom seemed to give him a foresight of his approaching death. Having therefore settled his church and put all things in the best order possible, he set out with certain zealous companions to preach to the savage infidel inhabitants of the northern parts of East Friesland. Having converted and baptized some thousands among them, he appointed the eve of Whit-Sunday to administer to the neophytes the sacrament of confirmation in the open fields in the plains of Dockum, near the banks of the little rivulet Bordne. He pitched there a tent, and was waiting in prayer the arrival of the new converts, when, behold, instead of friends, a band of enraged infidels appeared on the plain all in arms, and coming up, rushed into his tent. The servants that were with the holy martyr were for defending his life by fighting; but he would not suffer it, declaring that the day he had long waited for was come, which was to bring him to the eternal joys of the Lord. He encouraged the rest to meet, with cheerfulness and constancy, a death which was to them the gate of everlasting life. While he was thus employed, the Pagans attacked them sword in hand, and put them all to death. St. Boniface suffered in the seventy-fifth year of his age, on the 5th of June, in the year of Christ 755. With him were martyred fifty-two companions, of whom the principal persons were Eoban, bishop; Wintrung, Walter, and Adelhere, priests; Hamund, Strichald, and Bosa, deacons; Waccar, Gunderhar, Williker, and Hadulph, monks; the rest were laymen.