This poem, like other work by Browning (such as Fra Lippo Lippi), is set in the centuries of Italian city-states (14-17th centuries) where each city claims it own royal lineage; a Duke and Duchess, then, are not members of a larger hierarchy but rulers of a specific district. The Vatican held a lot of power, as did the Medici family. The Duke (possibly the Duke of Milan) is here negotiating with another ruling family from another city-state that has sent an ambassador to assess the legitimacy of the pending marriage of two royal city-state households (foreign governments, too, notably France, sought power through marriages and dowries). The mention of Fra Pandolf and of Claus of Innsbruck places the social and cultural context, in which royalty are patrons of the arts (more famous examples might be Michelangelo or Da Vinci, who had similar patronage for their work). The word “renaissance” could be used to define the cultural period, except that it is used too loosely and too widely to address the question.