In 1310, Henry VII, the newly elected Holy Roman Emperor, crossed the Alps into Lombardy in order to enforce his sovereign rights within Italy. Henry’s arrival was fervently welcomed by Dante, who hoped that this ruler would fulfil his messianic hopes for the creation of a supranational State, with political powers and authority that were completely separate from the Church. Dante’s philosophical justification for the political views that underpinned his support for Henry were elaborated in his treatise De monarchia, probably written sometime between Henry's arrival in Italy and his unexpected death in 1313, while laying siege to Naples. Early in this work, Dante, like a good scholastic, defines his terms: ‘Temporal monarchy, then, which men call “empire”, is a single sovereign authority set over all others in time […] and over those things which are measured by time’ (I, ii, 2; Dante 1995: 5). He then proceeds to outline one of his basic arguments in favour of a universal monarchy: God created diversity in mankind because the specific potentiality of man – that which set him apart from beasts – was his ‘intellectual potentiality or faculty’ (I, iii, 8; Dante 1995: 9); and this collective intellectual capacity can be realized only when the human race, in all its diversity, has been brought together under the peaceful rule of a single monarchy or empire (I, iii–iv). And only a single monarch, or emperor, can establish the universal peace necessary for mankind to fulfil its divine function (I, v). Just as the excellence of the whole transcends the excellence of its constituent parts, only when the totality of mankind has been brought under the sway of a single ruling power can it achieve the earthly felicity assigned to it by God (I, vi–vii): ‘mankind is most like God when it is ruled by one ruler, and consequently is most in harmony with God's intention’ (I, viii, 5; Dante 1995: 19).

Dante caps a tradition of political treatises that were inspired by the longstanding debate over the relative power of Church and State. What concerns me here is not primarily that conflict as such, but Dante's preoccupation with the nature and excercise of political power – questions of sovereignty and dominion – after the intellectual and territorial expansion of the thirteenth century.