	According to the chronicles of Thietmar of Merseburg, Otto III, who had been a friend and pupil of Adalbert, committed to a pilgrimage from Italy to St. Adalbert's tomb in Gniezno; in his attempt to extend the influence of Christianity in Eastern Europe, and to renew the Holy Roman Empire based on a federal concept (""renovatio Imperii Romanorum"") with the Polish and Hungarian duchies upgraded to eastern "federati" of the empire. As part of this policy he also invested Grand Prince Stephen I of Hungary with the king's crown (the Crown of Saint Stephen). 