In the period from 1050–1150 we see law and life ricocheting off each other, and rapid changes in both. Early fifth-century canon law provided a basis for imperial intervention in doubtful papal elections, legitimating Leo IX, who initiated the papal turn. In a number of areas the earliest papal jurisprudence provoked reform. The mismatch between law and life was a long-term result – in an age of urbanization! - of the post-Roman ruralization of Christianity. Ancient canon law was designed for city Christian communities concentrated around the bishop. It was ill-adapted to a world of isolated parish priests who could not be expected to maintain celibacy within marriage. Similarly, election of bishops by the ‘clergy and people’ was less practicable in a large rural diocese than in a concentrated urban community. The papal turn found expression in new legislation, notably about celibacy, which now meant something different from the celibacy required by late Antique papal law. But the new rules proved too simplistic, and further legal evolution followed. ‘Gratian’ expanded by his own commentary the meaning of canons – including papal decretals from late Antiquity – for his own age.