Adalbert is one of the most prominent figures of early Czech history. He was born in 956 to a Slavnik family, which was the most dangerous competitor of the ruling Premyslids. He obtained an excellent education and was appointed the second Prague archbishop. His attempt to revive spiritual purity in the Czech Lands was not successful (he spoke against marriage of priests, bigamy, selling of Christian captives to slavery) and therefore left for Rome. Adalbert returned shortly to Prague, where he founded a monastery in Břevnov, but after the slaughtering of the Slavniks (995) he left for Poland, from where he went on missions to pagan Prussians in Pomerania. In 997, during one his missions, he and his companions were murdered. He was canonized by Pope Silvester II just two years later. Prince Břetislav I brought the remains of St. Adalbert from Poland to the Prague Castle in 1039. St. Adalbert is a patron of winegrowers. He is portrayed as a bishop with a mitre, staff, palm branch, book, scale or paddle (with which he was allegedly hit by his murderers), sometimes with a spear, lance or arrows (the instruments of his torture) or an eagle (who supposedly watched over his body).