==Expanding nation states== 

 The phrase "... a time of expanding nation states ..." is wildly anachronistic.  Boniface lived at the height of the age of Feudalism.  Nobody thought in terms of 'nation states'.  Indeed the papacy and the Emperor were two institutions which worked against the idea of individual nations.  The contest was between the two swords, religious and civil, Church and Empire, and whether they were coordinate, or one was supreme. Italy and Rome in particular were beginning to enjoy the (quite ancient) idea of city-states.  I suggest that the phrase be deleted.