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).