Episcopate and exiles
Adalbert was chosen Bishop of Prague in 982, succeeding Bishop Dietmar, though he was still under canonical age. His efforts at reform and evangelization met persistent resistance from both the secular nobility and the clergy.
After about six years of limited success he withdrew, in 988, to Rome, where he lived for two years at the monastery of Saint Boniface and Alexis on the Aventine Hill. He returned to Bohemia in 992 and in 993 founded a monastery at Brevnov, but, frustrated again, returned to the Aventine in 995. Around the time of this second withdrawal, Duke Boleslaus II had Adalbert's brothers killed and the Slavnik family seat destroyed.
Missionary work and martyrdom
Released by Emperor Otto III, at whose court he stayed in 996, Adalbert was free to devote himself to the Christianization of pagan lands as a missionary bishop. He is reported to have traveled to Hungary, where tradition holds he baptized Duke Geza and his son Stephen at Esztergom.
In March 997 he came to the court of the Polish duke Boleslaw Chrobry at Gniezno and set out northward. After passing through Gdansk he entered Prussia, most likely in the region of Pomesania, and was killed on 23 April 997 while preaching among the Prussians. The accounts relate that after his death his head was cut off and impaled on a stake.
Veneration and relics
Adalbert was declared a saint, most likely on 29 June 999, in Rome. His body was ransomed, and the relics were solemnly brought into Prague on 24 August 1038.
He came to be honored with two elaborate shrines, in the Cathedral in Prague and in the Royal Cathedral of Gniezno, each of which claims to possess his relics; which of the bones are authentic is uncertain. After the martyrdom, Emperor Otto III traveled to Gniezno to venerate the relics and preside over the synod (the Congress of Gniezno, 1000) that established a new metropolis, and his veneration spread rapidly through the distribution of relics across Central Europe.
